Nutrition Education in the K-12 Curriculum: The Role of National Standards - Workshop Summary

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Structural Studies of Mixed Glass Former 0.35Na2O + 0.65[xB2O3 + (1 – x)P2O5] Glasses by Raman and 11B and 31P Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopies

The mixed glass former (MGF) effect (MGFE) is defined as a nonlinear and nonadditive change in the ionic conductivity with changing glass former composition at constant modifier composition. In this study, sodium borophosphate 0.35Na2O + 0.65[xB2O3 + (1 – x)P2O5], 0 ≤ x≤ 1, glasses which have been shown to exhibit a positive MGFE have been prepared and examined using Raman and 11B and 31P magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopies. Through examination of the short-range order (SRO) structures found in the ternary glasses, it was determined that the minority glass former, B for 0.1 ≤ x ≤ 0.7 and P for 0.7 ≤ x ≤ 0.9, is “overmodified” and contains more Na+ ions than would be expected from simple linear mixing of the binary sodium borate, x = 1, and sodium phosphate, x = 0, glasses, respectively. Changes in the intermediate range order (IRO) structures were suggested by changes in the NMR spectral chemical shifts and Raman spectra wavenumber shifts over the full composition range x in the Raman and MAS NMR spectra. The changes observed in the chemical shifts of 31P MAS NMR spectra with x are found to be too large to be caused solely by changing sodium modification of the phosphate SRO structural groups, and this indicates that internetwork bonding between phosphorus and boron through bridging oxygens (BOs), P–O–B, must be a major contributor to the IRO structure of these glasses. While not fully developed, a first-order thermodynamic analysis based upon the Gibbs free energies of formation of the various SRO structural units in this system has been developed and can be used to account for the preferential formation of tetrahedral boron groups, B4, by the reaction of B3 with P2 groups to form B4 and P3 groups, respectively, where the superscript denotes the number of BOs on these units, in these glasses. This preference for B4 units appears to be a predominate cause of the changing modifier to glass former ratio with composition x in these ternary MGF glasses and appears to be associated with the large negative value of the Gibbs free energy of formation of this group

Ionic Conductivity of Mixed Glass Former 0.35Na2O + 0.65[xB2O3 + (1 – x)P2O5] Glasses

The mixed glass former effect (MGFE) is defined as a nonlinear and nonadditive change in the ionic conductivity with changing glass former fraction at constant modifier composition between two binary glass forming compositions. In this study, mixed glass former (MGF) sodium borophosphate glasses, 0.35Na2O + 0.65[xB2O3 + (1 – x)P2O5], 0 ≤ x ≤ 1, have been prepared, and their sodium ionic conductivity has been studied. The ionic conductivity exhibits a strong, positive MGFE that is caused by a corresponding strongly negative nonlinear, nonadditive change in the conductivity activation energy with changing glass former content, x. We describe a successful model of the MGFE in the conductivity activation energy terms of the underlying short-range order (SRO) phosphate and borate glass former structures present in these glasses. To do this, we have developed a modified Anderson-Stuart (A–S) model to explain the decrease in the activation energy in terms of the atomic level composition dependence (x) of the borate and phosphate SRO structural groups, the Na+ ion concentration, and the Na+ mobility. In our revision of the A–S model, we carefully improve the treatment of the cation jump distance and incorporate an effective Madelung constant to account for many body coulomb potential effects. Using our model, we are able to accurately reproduce the composition dependence of the activation energy with a single adjustable parameter, the effective Madelung constant, that changes systematically with composition, x, and varies by no more than 10% from values typical of oxide ceramics. Our model suggests that the decreasing columbic binding energies that govern the concentration of the mobile cations are sufficiently strong in these glasses to overcome the increasing volumetric strain energies (mobility) caused by strongly increasing glass-transition temperatures combined with strongly decreasing molar volumes of these glasses. The dependence of the columbic binding energy term on the relative high-frequency dielectric permittivity suggests that the increased polarizability of the bridging oxygens connecting SRO tetrahedral boron units to phosphorus units causes further charge delocalization away from the negatively charged tetrahedral boron units, leading to a lowering of the charge density, and is the underlying cause of the MGFE

Residents Informing the Planning Process: Pleasant Valley and Its Natural Resources

As a society, we are slowly learning the importance of the interaction between the natural and built environments. We need a new model for planning and development that gives more weight to natural resource considerations than has traditionally occurred in the development process. An opportunity exists in Pleasant Valley to bring focus to natural resources in future planning efforts by tapping into the local knowledge of residents who know and love the land. Because the area will begin to urbanize in the near future, it is necessary to learn about the area before development occurs or people move away. The purpose of this project was to gather the local knowledge of natural resources and distill it into key findings to guide future plans

Goal Post Injuries in Soccer

Soccer is the most popular team sport worldwide, with approximately 40 million amateur participants. Most fa talities in soccer are related to player impact with the goal post. This study focuses on two case reports, a laboratory testing phase, and a pilot field testing phase of preventive equipment that can be used around the goal to prevent injury. Horizontal and vertical impact testing in the laboratory revealed impact force was di minished when the goal post was covered with protec tive padding (reduction of 31% and 63%) (P < 0.05). These data showed a statistically significant decrease in force at all temperatures. In the pilot field testing phase of the study, 471 games were monitored. Soccer teams participating in youth, teen, and adult soccer leagues were included in this phase of the study. During the 3-year study, there were seven player collisions with padded goal posts, and no injuries were recorded. The use of padded goal posts within the game of soccer has been documented to reduce the possibility of injury, both in the laboratory phase and in the pilot field testing phase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66584/2/10.1177_036354659502300316.pd

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Influence of Invasive Hybrid Cattails on Habitat Use by Common Loons

An invasive hybrid cattail species, Typha x glauca (T. x glauca), is rapidly expanding across the United States and Canada. Dense clonal stands of T. x glauca outcompete native wetland plants, reduce open-water habitats, and negatively affect native wetland plant diversity; however, effects of hybrid cattail expansions on native wildlife are still unclear. We used multiple surveys and single-season occupancy models to examine how the relative coverage of T. x glauca affected habitat use by common loons (Gavia immer) at 71 wetland sites in Voyageurs National Park, Minnesota, USA, during summer 2016. Delineated wetland sites (2 ha) were considered potential resource patches for common loons and positioned along a gradient of relative T. x glauca coverage. Detection of common loons was influenced negatively by the time of day surveys were conducted. Occupancy probabilities were greater at sites with deeper water levels, possibly indicating selection for areas with adequate water depths for pursuit-based foraging for fish. Contrary to our hypothesis, common loons appeared insensitive to the relative coverage of T. x glauca at wetland sites. Future research should focus on elucidating potential threshold-effects of T. x glauca expansions on additional loon demographic rates

FINE-SCALE TEMPERATURE PATTERNS IN THE SOUTHERN BOREAL FOREST: IMPLICATIONS FOR THE COLD-ADAPTED MOOSE

Moose (Alces alces) respond to warm temperatures through both physiological and behavioral mechanisms. Moose can reduce heat load via habitat selection when spatial and temporal variation exists within the thermal environment. We recorded operative temperatures (To) throughout the Kabetogama Peninsula of Voyageurs National Park, Minnesota for 1 year to describe seasonal patterns in the thermal environment available to moose and identify physical and landscape characteristics that affect To in southern boreal forests. Significant predictors of To varied by season and time of day and included vegetation cover type, canopy cover, and slope/aspect. Vegetation cover type influenced To during summer and fall afternoons with additional variation during summer afternoons explained by percent canopy cover. Slope/aspect was the main driver of To during winter and spring afternoons. Slope position was not a significant predictor of temperature, likely because of low topographic relief in our study area. The Tos were significantly warmer in open versus closed habitats during the day with the pattern reversed at night. Our results can be used to test if moose display a behavioral response to To at various spatial and temporal scales