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A novel laboratory curriculum is presented, developed around some common tasks of a laboratory researcher in chemistry: purification, synthesis, and measurement. The capstone of the sequence is an integrated laboratory, leading to a more independent research experience. Students who have completed this laboratory curriculum appear to perform comparably to previous students who completed a more traditional curriculum, based on their handling of American Chemical Society Exam questions and career placement. Introduction of the new curriculum has coincided with increased numbers of majors as well as increased participation in research, but attributing causation is complicated by the coincidental introduction of a new scholarship program.

A one-semester, introductory chemistry course is described that develops a primarily qualitative understanding of structure-property relationships. Starting from an atoms-first approach, the course examines the properties and three-dimensional structure of metallic and ionic solids before expanding into a thorough investigation of molecules. In addition to bonding, geometry, molecular orbitals, and intermolecular attractions, other structural topics are included, such as stereochemistry, conformation, and factors that influence the strength of Brønsted acids. Where appropriate, related considerations in biochemistry are highlighted. The course provides a common basis to majors and nonmajors for further study in chemistry and also serves as a platform to illustrate a variety of topics of current research interest.

The recent revision of undergraduate curricular guidelines from the American Chemical Society Committee on Professional Training (ACS-CPT) has generated interest in examining new ways of organizing course sequences both for chemistry majors and for nonmajors. A radical reconstruction of the foundation-level chemistry curriculum is presented in which content has been reorganized into three sequences: structure, reactivity, and quantitation. It is proposed that these three areas represent fundamental aspects of chemistry that cross traditional domains and allow students to more quickly appreciate the breadth of the field. An overview of these sequences in the chemistry curriculum at CSB/SJU is described.

Factors controlling the spread of invasive earthworms in Minnesota's Boundary Waters Canoe Area Wilderness are poorly known. Believed to have been introduced by anglers who use them as bait, invasive earthworms can alter the physical and chemical properties of soil and modify forest plant communities. To examine factors influencing earthworm distribution and abundance, we sampled 38 islands across five lakes to assess the effects of campsites, fire and entry point distance on earthworm density, biomass and species richness. We hypothesized that all three parameters would be greater on islands with campsites, lower on burned islands and would decrease with distance from the wilderness entry point. In addition to sampling earthworms, we collected soil cores to examine soil organic matter and recorded ground and vegetation cover. Campsite presence was the single most important factor affecting sampled earthworm communities; density, biomass and species richness were all higher on islands having campsites. Fire was associated with reduced earthworm density, but had no direct effects on earthworm biomass or species richness. Fire influenced earthworm biomass primarily through its negative relationship to groundcover and through an interaction with entry point distance. Entry point distance itself affected earthworm density and biomass. For islands with campsites, earthworm biomass increased with distance from the entry point. [ABSTRACT FROM AUTHOR]

Two related lines of research have gained traction in the social sciences during the past three decades. One examines the association between race and punishment, while a second investigates stratification and colorism, defined as discrimination based on skin tone. Yet rarely do scholars examine these issues together. The current study uses new data to investigate the association between offender's skin tone, Afrocentric facial features, and criminal punishment. More than 850 booking photos of black and white male offenders in two Minnesota counties were coded and then matched to detailed sentencing records. Results indicate that darker skin tone and Afrocentric facial features are associated with harsher sanctions and that the latter effect is particularly salient for white defendants. The findings add to existing work on skin tone and stratification and suggest that future research should consider other aspects of appearance, such as facial features, in the study of punishment and inequality.

This article describes an intervention for breast cancer survivors called Journal of My Medical Experiences in which participants engaged in reflective writing over six weeks. The 107 participants were encouraged to explore concerns and issues in a safe online environment. About half of the women posted writings to a website once a week or more; others logged on solely to read what others had written. A number of themes emerged as the women explored their feelings. We share some of those.

Atmospheric mercury is the dominant Hg source to fish in northern Minnesota and elsewhere. However, atmospherically derived Hg must be methylated prior to accumulating in fish. Sulfate-reducing bacteria are thought to be the primary methylators of Hg in the environment. Previous laboratory and field mesocosm studies have demonstrated an increase in methylmercury (MeHg) levels in sediment and peatland porewaters following additions of sulfate. In the current ecosystem-scale study, sulfate was added to half of an experimental wetland at the Marcell Experimental Forest located in northeastern Minnesota, increasing annual sulfate load by approximately four times relative to the control half of the wetland. Sulfate was added on four separate occasions during 2002 and delivered via a sprinkler system constructed on the southeast half (1.0 ha) of the S6 experimental wetland. MeHg levels were monitored in porewater and in outflow from the wetland. Prior to the first sulfate addition, MeHg concentrations (filtered, 0.7 microm) were not statistically different between the control (0.47 +/- 0.10 ng L(-1), n = 12; mean +/- one standard error) and experimental 0.52 +/- 0.05 ng L(-1), n = 18) halves. Following the first addition in May 2002, MeHg porewater concentrations increased to 1.63 +/- 0.27 ng L(-1) two weeks after the addition, a 3-fold increase. Subsequent additions in July and September 2002 did not raise porewater MeHg, but the applied sulfate was not observed in porewaters 24 h after addition. MeHg concentrations in outflow from the wetland also increased leading to an estimated 2.4x increase of MeHg flux from the wetland. Our results demonstrate enhanced methylation and increased MeHg concentrations within the wetland and in outflow from the wetland suggesting that decreasing sulfate deposition rates would lower MeHg export from wetlands.