Bryn Mawr College
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Using a Drone as a Vehicle for Learning
Get PDFThis session describes a freshman seminar in which a drone was used in a mock humanitarian aid mission to map a disaster area and deliver aid. As well as teaching teamwork skills, the mission became a focal point for learning activities relating to intercultural understanding and the value of multiple perspectives. Since drones have applications in many fields, this class may be a useful model for other experiential classes in the Humanities. Participants will have an opportunity to try a flight simulator and will leave the workshop with an idea of what is involved in conducting such a class
Listening to equity-seeking perspectives: how students’ experiences of pedagogical partnership can inform wider discussions of student success
Get PDFDiscussions in higher education have proliferated in recent years regarding not only how to recruit a greater diversity of students but also how to support their success. The voices of students themselves, particularly those students traditionally underrepresented in and underserved by higher education, have important contributions to make to these discussions. This article draws on a larger study of the perspectives of undergraduate students who identify as members of equity-seeking groups (e.g., students who are racialized, LGBTQ+ and first generation) and who have collaborated with faculty in a bi-college, classroom-focused, pedagogical partnership program in the United States. Using constant comparison/grounded theory, I analyzed these students’ responses to a question about how participating in this program affected their sense of themselves as students. The themes that emerged across students’ responses included how participation in pedagogical partnership (1) fosters important affective experiences in relation to all faculty and to fellow students, (2) informs students’ academic engagement in their own classes and (3) contributes to students’ sense of their evolution as active agents in their own and others’ development. Both affirming and expanding established understandings of what contributes to student success presented in the literature on belonging, engagement and persistence, these themes have implications for how we might support the success of a diversity of students both within and beyond formal pedagogical partnership
Indoleamine 2,3-Dioxygenase and Its Therapeutic Inhibition in Cancer
Get PDFThe tryptophan catabolic enzyme indoleamine 2,3-dioxygenase-1 (IDO1) has attracted enormous attention in driving cancer immunosuppression, neovascularization, and metastasis. IDO1 suppresses local CD8 + T effector cells and natural killer cells and induces CD4 + T regulatory cells (iTreg) and myeloid-derived suppressor cells (MDSC). The structurally distinct enzyme tryptophan dioxygenase (TDO) also has been implicated recently in immune escape and metastatic progression. Lastly, emerging evidence suggests that the IDO1-related enzyme IDO2 may support IDO1-mediated iTreg and contribute to B-cell inflammed states in certain cancers. IDO1 and TDO are upregulated widely in neoplastic cells but also variably in stromal, endothelial, and innate immune cells of the tumor microenviroment and in tumor-draining lymph nodes. Pharmacological and genetic proofs in preclinical models of cancer have validated IDO1 as a cancer therapeutic target. IDO1 inhibitors have limited activity on their own but greatly enhance “immunogenic” chemotherapy or immune checkpoint drugs. IDO/TDO function is rooted in inflammatory programming, thereby influencing tumor neovascularization, MDSC generation, and metastasis beyond effects on adaptive immune tolerance. Discovery and development of two small molecule enzyme inhibitors of IDO1 have advanced furthest to date in Phase II/III human trials (epacadostat and navoximod, respectively). Indoximod, a tryptophan mimetic compound with a different mechanism of action in the IDO pathway has also advanced in multiple Phase II trials. Second generation combined IDO/TDO inhibitors may broaden impact in cancer treatment, for example, in addressing IDO1 bypass (inherent resistance) or acquired resistance to IDO1 inhibitors. This review surveys knowledge about IDO1 function and how IDO1 inhibitors reprogram inflammation to heighten therapeutic responses in cancer
Reduced orexin system function underlies resilience to repeated social defeat stress
Get PDFExposure to stress increases the risk of developing affective disorders such as depression and post-traumatic stress disorder (PTSD). However, these disorders occur in only a subset of individuals, those that are more vulnerable to the effects of stress, whereas others remain resilient. The coping style adopted to deal with the stressor, either passive or active coping, is related to vulnerability or resilience, respectively. Important neural substrates that mediate responses to a stressor are the orexins. These neuropeptides are altered in the cerebrospinal fluid of patients with stress-related illnesses such as depression and PTSD. The present experi- ments used a rodent social defeat model that generates actively coping rats and passively coping rats, which we have previously shown exhibit resilient and vulnerable profiles, respectively, to examine if orexins play a role in these stress-induced phenotypes. In situ radiolabeling and qPCR revealed that actively coping rats expressed significantly lower prepro-orexin mRNA compared with passively coping rats. This led to the hypothesis that lower levels of orexins contribute to resilience to repeated social stress. To test this hypothesis, rats first underwent 5 d of social defeat to establish active and passive coping phenotypes. Then, orexin neurons were inhibited before each social defeat for three additional days using designer receptors exclusively activated by designer drugs (DREADDs). Inhibition of orexins increased social interaction behavior and decreased depressive-like behavior in the vulnerable population of rats. Indeed, these data suggest that lowering orexins promoted resilience to social defeat and may be an important target for treatment of stress-related disorders
Help (not) wanted: Neo-liberal discourses of leadership against community knowledge and control in comparative context
Get PDFThis article compares two neo-liberal education reform activities that are not often studied in tandem: alternative teacher certification in the USA, as explored through Teach for America, and the growing international service learning movement. Guided by the Movement for Black Lives’ call for a world where those “most impacted in our communities control the laws, institutions, and policies that are meant to serve us,” the authors explore the ways in which programs’ neo-liberal justifications obscure the authority, history, and agency of the communities they purport to serve, while convincing people outside of the community that those within are benefitted. The comparisons drawn highlight the ways in which deficit orientations permeate different local and global contexts to perpetuate and normalize privatization and the wresting of control from local communities. In making this comparison, the authors aim to better understand what these programs have in common: a white supremacist world view at once unstated and pervasive, which reinforces harmful ideas about what it is to respond to the purported needs and desires of others, not expressed in their own terms. This globalization of “helping” may increase the difficulty of those targeted by such “help” to speak in their own terms
Tuning the Néel Temperature of Hexagonal Ferrites by Structural Distortion
No full textTo tune the magnetic properties of hexagonal ferrites, a family of magnetoelectric multiferroic materials, by atomic-scale structural engineering, we studied the effect of structural distortion on the magnetic ordering temperature (TN) in these materials. Using the symmetry analysis, we show that unlike most antiferromagnetic rare-earth transition-metal perovskites, a larger structural distortion leads to a higher TN in hexagonal ferrites and manganites, because the K3 structural distortion induces the three-dimensional magnetic ordering, which is forbidden in the undistorted structure by symmetry. We also revealed a near-linear relation between TN and the tolerance factor and a power-law relation between TN and the K3 distortion amplitude. Following the analysis, a record-high TN(185 K) among hexagonal ferrites was predicted in hexagonal ScFeO3 and experimentally verified in epitaxially stabilized films. These results add to the paradigm of spin-lattice coupling in antiferromagnetic oxides and suggests further tunability of hexagonal ferrites if more lattice distortion can be achieved
Structural insight into substrate and product binding in an archaeal mevalonate kinase
No full textMevalonate kinase (MK) is a key enzyme of the mevalonate pathway, which produces the biosynthetic precursors for steroids, including cholesterol, and isoprenoids, the largest class of natural products. Currently available crystal structures of MK from different organisms depict the enzyme in its unbound, substrate-bound, and inhibitor-bound forms; however, until now no structure has yet been determined of MK bound to its product, 5-phosphomevalonate. Here, we present crystal structures of mevalonate-bound and 5-phosphomevalonate-bound MK from Methanosarcina mazei (MmMK), a methanogenic archaeon. In contrast to the prior structure of a eukaryotic MK bound with mevalonate, we find a striking lack of direct interactions between this archaeal MK and its substrate. Further, these two MmMK structures join the prior structure of the apoenzyme to complete the first suite of structural snapshots that depict unbound, substrate-bound, and product-bound forms of the same MK. With this collection of structures, we now provide additional insight into the catalytic mechanism of this biologically essential enzyme