An ethnographic investigation of the process of change in students\u27 environmental identity and pro-environmental behavior in an Environmental Science course

In recent years, the Environmental Science course has become increasingly integrated into the high school curriculum as a component of the core curriculum, an AP course, or as an elective (Edelson, 2007); however, little research has been conducted to evaluate the course\u27s effectiveness in developing students\u27 understanding of their relationship with the environment (Zelezny, 1999). Therefore, this ethnographic study at a public high school in the Northeastern United States focuses on the teacher\u27s goals for the Environmental Science course, how students respond to the enactment of these objectives during activities in the classroom, and how the class impacts students\u27 views of their relationship with the environment and their pro-environmental behavior. A sociocultural approach is utilized to explore how students\u27 environmental identities, their interactions with the course content, as well as their social interactions affect their experiences in the Environmental Science classroom. The study\u27s conceptual framework is based upon Kempton and Holland\u27s (2003) stages of environmental identity development, as well as symbolic interactionist theories of emotion. The participants in this study are an Environmental Science teacher and the 10-12th grade students (N=17) in her semester-long elective, Environmental Science. The researcher collected data for a period of six months during the spring semester of 2009, attending class on a daily basis. Data was collected through participant observation, videotaping, interviews, cogenerative dialogues, and various surveys. The objectives for the Environmental Science course explored in this research include the role of science content knowledge and critical thinking as students are exposed to new environmental information; developing students\u27 emotional connection with environmental issues; influencing students\u27 environmental behavior; and empowering students to feel that they can make a difference through their own actions. Through presentation of the students\u27 reactions to their experiences in the classroom, the results of this study provide new information for educators working with students to help them define their relationship with the environment by illuminating the elements of various activities that are effective for individual students, as well as factors that may be prohibitive. Findings therefore provide insight for science teachers designing and incorporating environmental activities into the high school curriculum

Preferential infection and depletion of Mycobacterium tuberculosis–specific CD4 T cells after HIV-1 infection

HIV-1 preferentially infects M. tuberculosis-specific CD4+ T cells due to their increased production of IL-2

Desferrithiocin is a more potent antineoplastic agent than desferrioxamine

Desferrithiocin (DFT) is an orally effective Fe chelator, with a similar high affinity and selectivity for Fe to desferrioxamine (DFO), which has been shown clinically to possess antineoplastic activity. In this study, DFT was assessed for antineoplastic potential in hepatocellular carcinoma cell lines (HCC). This was done as there are few treatments for this aggressive neoplasm. The effects of DFT on cell proliferation, cell cycle progression, Fe uptake and toxicity were examined. To establish whether DFT was selective for cancer cells a comparison was made with normal (non-proliferating) hepatocytes and non-tumorigenic (proliferating) fibroblasts (SWISS-3T3). DFT was a potent inhibitor of HCC proliferation (IC(50)∼40 μM). DFO also inhibited HCC proliferation under the same conditions, but was much less active (IC(50)=110 – 210 μM). When saturated with Fe, the activity of DFT, like DFO, was greatly diminished, suggesting it may act by depriving the cells of Fe or inactivating essential Fe pool(s). Indeed DFT rapidly decreased Fe uptake from Tf-(59)Fe by hepatoma cells and also by normal hepatocytes. However, DFT (and DFO) had much less effect on cell survival in hepatocytes and fibroblasts than in hepatoma cells. DFT may, like DFO, inhibit the cell cycle in the S phase of DNA synthesis. Both chelators showed low toxicity. These results indicate that DFT has potent antineoplastic activity in HCC. Further investigation into the DFT class of Fe chelators seems warranted, particularly in view of its high activity in relation to DFO, a chelator which is already in clinical trial for neuroblastoma