Stem-net

STEM-NET

STEM

 

 

STEM-NET is a collaboration of 23 campuses supported by the CSU Chancellor’s Office. Its vision is to make the CSU a worldwide leader in increasing the pipeline, preparation, graduation and employment of diverse STEM students. The mission is to enable CSU STEM leaders to share expertise and leverage university-wide opportunities to foster the implementation of global best practices for students and faculty in pedagogy, learning and research within the CSU.

Saving Coral Reefs by Using a Sea Anemone as a Laboratory Model for Studying Host-Microbe Interactions

sea anemone called Exaiptasia pallida (commonly referred to as “Aiptasia”)
 

Coral reefs are among the most diverse ecosystems in the world and are home to a large variety of marine organisms. In addition to their ecological importance, coral reefs have significant economic, aesthetic and medicinal value, including the compounds for biomedical research and therapies. At present, natural and anthropogenic stresses threaten the health of coral reefs worldwide. Global climate change is driving the rise in ocean temperatures, leading to coral bleaching and death. Finding the means for corals to adapt to and survive in higher temperatures requires a more thorough understanding of their physiology as a whole—the corals themselves, and all the microorganisms they associate with.

At California State University, Chico, Dr. Cawa Tran, assistant professor of biological sciences, and her research team of master’s and undergraduate students look toward the potential for bacteria to help animals increase their heat tolerance. For the ease of laboratory manipulation, they experiment with a well-established model organism, a sea anemone called Exaiptasia pallida (commonly referred to as “Aiptasia”), that is related to corals. Both are symbiotic cnidarians (a group that also contains jellyfish) that will expel algae in response to stress.

Jamie Sydnor, the most senior graduate student in the Tran laboratory, has examined the community of bacteria that Aiptasia usually associates with (its microbiome) and how that community stochastically changes when the animal experiences heat stress. To better understand how these bacteria are initially integrated into the animal, Dr. Tran and her research team are collaborating with Dr. Joseph Greene, professor of sustainable manufacturing and mechanical engineering at Chico State, and a team of four mechanical engineering undergraduates (Thomas Cunningham, Emily Williams, Alize Hall and Sultan Alharbi). Together, they are designing a novel microfluidics chamber to enclose live anemones with flowing seawater under a microscope that will allow video recording of fluorescently labeled bacteria entering and establishing residence within these anemones in a process known as colonization.

The long-term goal of the Tran laboratory is to identify specific bacteria that can tolerate higher temperatures and, in turn, enable their animal host to endure these higher temperatures and survive in the face of global climate change. These beneficial microbes may serve as marine probiotics to help corals. Caution must be taken before manipulating corals and their microbiomes in nature; therefore, by testing heat-tolerant capabilities in a laboratory model like Aiptasia, Tran and her students can use this information to explore the potential of improving coral health with the aid of heat-resistant bacteria. This experimental manipulation of microbes, communities and their hosts is referred to as microbiome engineering, which has been used in both agricultural practices and human medicine. The Tran laboratory is attempting to harness the power of microbiome engineering to enable more thermotolerant animals. This research has inspired new training for Chico State students in biology and engineering to use modern biotechnological tools to understand animal-microbe interactions and help save coral reefs.

Transformative Inclusion in Postsecondary STEM: Toward Justice

People enjoying an outdoor meeting
 

What would it mean for a university STEM department to embody the “serving” in its Hispanic Serving Institution (HSI) designation? Although the HSI label is based on enrollment data, TIPS Towards Justice proposes a definition of Hispanic-serving in terms of culture and outcomes. With partners from other STEM disciplines, it will develop, pilot and test a two-year pathway (the TIPS Pathway) for academic departments to move toward a truly Hispanic-serving vision of a radically inclusive STEM culture, leading to demonstrably equitable outcomes (including graduation and persistence rates).

A recently recognized HSI, Sonoma State University enrolls a growing Latinx student population (31.2 percent in the 2018 U.S. Department of Education dataset). The Department of Mathematics and Statistics is committed to embracing its critical role in the realization of a truly equitable STEM community at Sonoma State and to contributing to a transformation of the culture of the mathematical sciences and STEM communities more broadly. Current data clearly show opportunity gaps for Hispanic students in mathematics and statistics at Sonoma State, such as GPA differentials in math major courses and math/stats majors where the enrollment of Hispanic students is 21 percent (compared with 31 percent at Sonoma State, 38 percent in California and 26 percent in Sonoma County).

The obstacles to full, equitable participation and success in STEM pursuits are legion, and mathematics is at the heart of many. Transformation requires math and other STEM departments to confront their:

  • Pedagogy that privileges some backgrounds over others.
  • Conceptions of mathematics and science that connect with some cultures more than others.
  • Prevalent cultural beliefs and messages about who belongs in mathematics and science.
  • Assumptions of student preparation that are in fact not widely or equitably available.
  • Widely held beliefs that mathematics and science are culture-neutral or even culture-free.
  • Lack of conversation and understanding about ways in which identity affects students’ engagement in STEM disciplines.
  • Reluctance to acknowledge the roles that STEM subjects can play in perpetuating unjust systems, and to address STEM possibilities for confronting and challenging such systems.

During the first two years of the proposed five-year project, the mathematics and statistics department, with partners in all STEM disciplines and local community colleges, will develop a guided pathway for STEM departments to follow in transforming their practice. During the third and fourth years, additional STEM departments at Sonoma State will engage with the pathway to transform their own outcomes and approaches to culture. TIPS leadership will revise the pathway based on feedback and results from both rounds of implementation and will publish results on the web during the fifth year.

TIPS Towards Justice will study effective STEM education reform that embraces “serving” at Hispanic-Serving Institutions, investigating the effects of department-level deep equity work through novel research in two areas: instructional and institutional practices that truly serve Latinx student identities. TIPS Towards Justice will fill a gap in research about students’ experiences of marginalization and belonging in university settings, especially about instructional and institutional practices that reduce marginalization and increase students’ sense of belonging. Many entrenched STEM teaching practices and institutional procedures, policies and conventions continue to disadvantage students who are historically marginalized in STEM. To finally build equitable opportunity for success in STEM, it is crucial to understand these effects on marginalization and belonging. A second area of focus is the impact of department-level implementation of Culturally Responsive Pedagogies (CRPs) through equity-focused lesson study on students’ sense of belonging and their persistence in STEM. TIPS Towards Justice will investigate and advance research on students’ sense of belonging when they consistently experience CRPs and identity-affirming episodes across a range of STEM courses and in their broader department experience.

Apply Mathematical Models and Computational Simulations to Address Fertility Problems

 Dr. Julie Simons at California State University Maritime Academy and students work on laptops
 

Applied mathematicians see complex problems through the lens of modeling. Keen modelers view intractable problems for laboratory scientists as exciting opportunities of exploration. Such problems are often at the interface of many branches of science and mathematics, providing opportunities for collaboration and working with students from a broad range of backgrounds.

The research group led by mathematician Dr. Julie Simons at California State University Maritime Academy is one such collaborative effort, bringing Cal Maritime students and University of California, Berkeley, scientists together to understand problems in fertility. Gillian Hooper and Alex Rosenberger, juniors in mechanical engineering, are working on developing and running large-scale simulations of sperm swimming in groups near a spherical surface that mimics the surface of the egg.

Sperm motility is a major indicating factor for fertility potential and is driven by undulating flagella. Sperm typically swim in viscous fluids that, to a human, would feel like moving through honey or molasses. Plus, elastic polymers in the fluid are like a maze of connected springs that can both entrap sperm and propel sperm in different directions. A dense matrix of such elastic polymers surrounds the egg that sperm attempt to fertilize.

The multibillion-dollar fertility industry has long recognized issues surrounding sperm motility, and most treatments are targeted toward women. A surprising amount of the basic science involved in sperm motility is still unknown. In particular, modeling of viscoelastic fluids is notoriously complicated and until recently, some models were considered intractable because of high computational costs. Yet, fertility costs and infertility problems are becoming increasingly important. With climate change, scientists are facing mounting problems that often require fertility interventions, including food chain security and sustainable agriculture as well as global declines in biodiversity and new conservation approaches.

An interesting aspect of sperm behavior is the sperm of some species swim cooperatively in groups to effectively reach the egg. Studying sperm motility for populations and near surfaces in detail is now experimentally possible through high-resolution imagery. Mathematical and computational models have the potential to measure quantities involving forces, power and efficiency that simply cannot be measured in the laboratory.

The Simons team is trying to explain the fundamental science of how sperm reach the egg by extending computational models previously developed by Dr. Simons and her collaborators at Tulane University to more biologically relevant frameworks. These include investigating the motility of sperm populations and swimming near surfaces to elucidate whether cooperative swimming behavior is advantageous from a fluid mechanics perspective and how fluid elasticity and surfaces affect swimming behavior. This is important for understanding the evolutionary aspect of sperm development across species as well as fertility issues within species. Next summer, Hooper and Rosenberger will be validating and refining their model results by performing new laboratory experiments in the lab of Dr. Polina Lishko at UC Berkeley using human and rodent sperm and high-speed digital cameras.