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The purpose of this qualitative research study was to explore the emotions, outcomes, and interpersonal relationship development of high school aged students who participated in a three-week intensive engineering apprenticeship program (EAP) during the summer of 2019. This EAP introduces students to engineering by placing them in teams and asking them to build an underwater vehicle that can complete a timed obstacle course. Program mentors provide minimal lecture based instruction and focus on encouraging each team to create their own unique design. The primary purpose of the EAP is to increase student interest in engineering by improving student understanding of the engineering profession and student exposure to discipline specific mentors. This exploratory study was conducted to gain insights into how informal engineering outreach programs affect high school age students’ interest in pursuing engineering in college. Engineering outreach programs are implemented for a variety of reasons including: (1) encouraging young students to select an engineering career, thereby building a pipeline of competent students and workers, (2) engaging community members in engineering as a way to foster positive feelings towards an institution, and (3) introducing a diverse range of young students to engineering disciplines as a way to improve diversity within the field. Methods to assess outreach programs commonly rely on self-reported measures through immediate and/or delayed self-reported surveys, short interviews, teacher and mentor interviews and surveys, and program enrollment data. While these assessment methods likely provide sufficient quantitative data to justify an outreach program to financial stakeholders, we believe that more in-depth assessment of student outcomes is needed to inform the design and development of engineering outreach programs that are culturally transformative. In this study we examined how students participated in and built intra-team working relationships within the three week EAP using an approach informed by ethnographic research methods. Data consisted of daily reflective journal entries that were documented by a graduate student researcher embedded in a student team, as well as research notes detailing written materials produced by students and images of the underwater vehicles. In accordance with an approved IRB protocol, de-identified data were segmented, coded using in vivo codes, and then recombined during multiple successive coding passes to develop themes that describe common threads relating student experiences in the program. The findings provide insights into how students (a) engaged with the outreach program tasks, (b) developed relationships with other members of their assigned teams and program mentors, (c) worked through the engineering design process both individually and as a team, and (d) worked to achieve stated outreach program goals and outcomes. The findings of this study are important for developing deeper understandings about how high school age students experience intensive engineering outreach programs that are designed to introduce them to real-world engineering design and development. Findings can be used to inform new approaches for assessing engineering outreach programs effectiveness.

Astronauts traveling or researching in space are subject to a harsh environment that includes high levels of ionizing radiation and microgravity. Ionizing radiation is dangerous to overall health because it causes double-stranded DNA breaks, increases the production of free radicals or reactive oxygen species, and leads to an enhanced risk of cardiovascular disease and cancer over a person’s lifetime. Similarly, microgravity is hazardous to astronaut health because humans require gravity to maintain a healthy heart and muscular and vascular systems. Both ionizing radiation and microgravity have been studied individually in previous research, but there is a lack of information on how these stressors work in combination to damage cellular health. To simulate the spaceflight radiation environment, Utah State University’s Space Survivability Test Chamber was used to irradiate mouse skeletal muscle cells with doses similar to what astronauts will be exposed to on a Mars mission. Microgravity was simulated within the radiation test chamber by designing a custom miniature rotary cell culture system. This device rotates muscle cells growing on polystyrene microcarrier beads so that the cell clusters remain suspended at their terminal settling velocity. The mouse muscle cells irradiated with a long-term spaceflight dosage exhibited significant amounts of double-stranded DNA damage as well as significantly increased production of reactive oxygen species compared to the short-term mission models. The combined model of ionizing radiation and microgravity designed here is more representative of the spaceflight environment than either condition alone. Our model is a valuable platform that can be used to study the effects of space travel on a variety of cell types and test potential treatments.

Muscular atrophy is a serious issue for extended spaceflight. Understanding and preventing the role of ionizing radiation in skeletal muscle loss would preserve the strength and endurance of astronauts and enable longer duration space travel and exploration. Irradiation was performed in the USU material physics group's Space Suvivability Test Chamber. C2C12 and CRL-1999 cells were exposed to dosages ranging from 0.5 - 36.8 Gy. Cell viability and growth rate were measured immediately following irradiation.

Muscular atrophy, defined as the loss of muscle tissue, is a serious issue for immobilized patients on Earth and in human spaceflight, where microgravity prevents normal muscle loading. Developing countermeasures for atrophy in spaceflight will require extensive screening of pharmaceuticals for efficacy, safety, contraindications, and dosage schedule. Due to the cost of spaceflight and limited crew time aboard the International Space Station, high throughput screening of pharmaceuticals under real microgravity conditions is not feasible. While traditional ground-based atrophy studies using the rodent hind-limb unloading model are effective at inducing physiological changes similar to spaceflight, they are not suited for first round screening of novel therapeutics due to resource and regulatory challenges. Additionally, these ground-based studies do not account for the high levels of ionizing radiation experienced in spaceflight that may increase atrophy. Here, we present a protocol to combine both microgravity and radiation using an in vitro ground-based model of microgravity with a rotary cell culture system combined with Utah State University’s Space Survivability Test Chamber (SSTC). To model the levels of ionizing radiation received by astronauts in space, murine C2C12 cells were cultured in standard tissue culture well plates and exposed to Strontium 90 in both their undifferentiated and differentiated states using the SSTC. We hypothesize that cells will show a significant loss of viability when exposed to a dosage of approximately 4.0 Gy, the LD50 for most human tissue. Changes after exposure to radiation were indicated by cell viability counts and morphology characterization. To model the microgravity conditions on the International Space Station, a custom rotary cell culture system was designed to be compatible with the SSTC. We hypothesize that combining both microgravity and radiation will lead to a greater biosimilarity for ground-based atrophy models. Contrary to expectations, undifferentiated cells exposed to radiation did not experience a significant loss in viability withstanding doses up to 38 Gy. Irradiated differentiated cells followed a lethal dosage curve as expected to reach 50% viability at approximately 4.0 Gy. Ground-based simulation of microgravity and radiation will provide a valuable platform for drug discovery and an understanding of the multiple mechanisms underlying muscular atrophy.

As longer space missions become more desirable to public and private institutions, the physiological impact on astronauts must be considered. One of the primary concerns for those spending time in low gravity and high radiation environments is muscle atrophy. A major cause of muscular atrophy is oxidative stress which is amplified by increased levels of ionizing radiation during spaceflight. Additionally, high levels of radiation can damage DNA, increasing the risk of cancer. Utah State University’s Space Environment Test Facility was used to irradiate C2C12 myoblasts and human vascular endothelial cells with a dosage mimicking that on the International Space Station and a 3-year deep space mission. Cell changes due to increased levels of radiation were characterized with fluorescent imaging for H2AX, a marker of double stranded DNA damage, and Trypan blue viability staining.

Introduction: Age related macular degeneration (AMD) is the leading cause of blindness in developed countries and accounts for nearly 10% of vision loss around the world. One major difficulty in studying AMD is modeling the retinal pigment epithelium (RPE) in vitro. The RPE is a single layer of cells that supports photoreceptors by providing nutrients and filtering waste products. RPE cells grow on the acellular Bruch’s membrane, which sits directly superior to the choroid layer. RPE have a characteristic dark pigment and grow in tight polygonal cell junctions. When grown in tissue culture flasks, these characteristics are not exhibited. In this study, spider silk coated substrates were used to replicate the surface chemistry of Bruch’s membrane and promote RPE growth, morphology, and differentiation. Materials and Methods: RPE cells were cultured in a T25 cell culture flasks until a concentration of 4.5x10^5 cells/ mL was reached. Cells were maintained using DMEM-F12 nutrient medium with 10% FBSand 10,000 units/ mL penicillin. A freestanding, semipermeable membrane was made using MaSp1 spider silk protein and inoculated with RPE cells. The cells were maintained using the same media for the first two days, then changed to a 5% FBS solution to prevent cell overgrowth. Cell confluency was measured daily using light microscopy; SEM images were captured after 13 weeks. Transepithelial electrical resistance (TEER) was measured weekly using a World Precision Instruments EVOM2 and STX2/Endohm 24Snap. Cells grown on spider silk showed similar characteristics to those grown on standard tissue culture plates. Cells did not pigment in the time period measured, but had similar confluency and morphology. After 5 weeks, the TEER suggested that there was no significant difference in the tight junction formation. Discussion: The spider silk protein shows promise as a substrate for RPE cell growth. Further research may show advantages in cell characterization using spider silk compared to tissue culture flasks. Spider silk coated permeable membranes may lead to a polarized RPE monolayer. Layering protein additives (collagen I-V, fibronectin and vascular endothelial growth factor (VEG-F)) may lead to better RPE cell differentiation.