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Good education requires student experiences that deliver lessons about practice as well as theory and that encourage students to work for the public good—especially in the operation of democratic institutions (Dewey 1923; Dewy 1938). We report on an evaluation of the pedagogical value of a research project involving 23 colleges and universities across the country. Faculty trained and supervised students who observed polling places in the 2016 General Election. Our findings indicate that this was a valuable learning experience in both the short and long terms. Students found their experiences to be valuable and reported learning generally and specifically related to course material. Postelection, they also felt more knowledgeable about election science topics, voting behavior, and research methods. Students reported interest in participating in similar research in the future, would recommend other students to do so, and expressed interest in more learning and research about the topics central to their experience. Our results suggest that participants appreciated the importance of elections and their study. Collectively, the participating students are engaged and efficacious—essential qualities of citizens in a democracy.
Bats are important but understudied pollinators in the Palaeotropics, and much about their interactions with night-blooming, bat-pollinated plant species is still unknown. We compared visitation times to flowering and fruiting plant resources by nectarivorous bat species (obligate pollinators) and frugi-nectarivorous bat species (facultative pollinators) throughout the night to examine the temporal variability that occurs within Pteropodidae foraging. Timing of pollination is an important determinant of plant reproductive success and more temporally restrictive than fruit dispersal. We netted 179 nectarivorous bats and 209 frugi-nectarivorous bats across 367 total mist-net h at five plant species providing floral resources and six plant species providing fruit resources. We found that all three nectarivorous bat species in southern Thailand forage significantly earlier in the evening (20h30 versus 22h00), and over a significantly shorter time interval (1.73 h versus 3.33 h), than do the five most commonly netted frugi-nectarivorous species. These results indicate that the two feeding guilds may be imposing different selective pressures on bat-pollinated plant species and may comprise different functional groups. We propose that the observed differences in bat foraging times are due to temporal constraints imposed by the rewards of the plant species that they visit.
Being able to anticipate future needs for health services presents a challenge for health planners. Using existing population projections, two models are presented to estimate the demand for hospital beds in regions of Manitoba in 2020. The first, a current-use projection model, simply projects the average use for a recent three-year period into the future. The second, a 10-year trend analysis, uses Poisson regression to project future demand. The current-use projection suggests a substantial increase in the demand for hospital beds, while the trend analysis projects a decline. The last projections are consistent with ongoing increases in rates of day surgeries and declines in lengths of stay. The current-use projections need to be considered in the context of relatively low occupancy rates in rural hospitals and previous research on appropriateness of stays in acute care hospitals. If measures are taken to ensure more appropriate use of acute care hospital beds in the future, then the current-use projections of bed shortages are not a cause for concern.
In most contaminated soils and mine tailings, mercury (Hg) is not readily available for plant uptake. A strategy for inducing Hg mobilization in soils to increase accumulation potential in plants was investigated to enhance Hg phytoremediation. Accumulation of Hg in the nickel hyperaccumulator Berkheya coddii, the salt-tolerant Atriplex canescens, and the nonaccumulators Brassica juncea and Lupinus sp. was studied by pot trials containing mine tailings treated with either soluble Hg or sulfur-containing ligands. Accumulation of Hg in shoots of B. coddii and A. canescens after addition of soluble Hg was lower than 10 mg/kg dry weight. The addition of ammonium thiosulfate (NH4S2O3) to tailings mobilized Hg in substrates, as indicated by the elevated Hg concentrations in leachates from the pots of both species. Ammonium thiosulfate caused a significant increase in the Hg concentration in shoots of B. juncea. Conversely, Hg translocation to Lupinus sp. shoots was significantly reduced in the presence of this ligand. Mass balance calculations revealed a significant fraction of Hg was lost from the system. This unaccounted-for Hg may indicate Hg volatilization. The results suggest that there is potential for induced plant Hg accumulation for phytoremediation of Hg-contaminated sites. Issues of Hg leaching and volatilization, however, need to be addressed before this technology can be implemented in the field.
A one year follow-up is reported of a randomized clinical trial with
generalized anxiety disorder (GAD) in which the main comparison was between
analytic psychotherapy (AP) and cognitive therapy (CT), each delivered at
weekly or fortnightly intervals over a six month period. CT was found to be
significantly more effective than AP. However, GAD is a chronic and
relapsing condition and follow-up data are needed to assess the durability
of improvement and the possibility that the benefits of analytic
psychotherapy may be more apparent over the longer term. Data were
collected in three areas: (1) symptomatology and overall improvement;
(2) medication usage and contact with GPs; and (3) attitudes to therapy. CT
was clearly superior to AP on the main outcome measures and only a minority
of AP patients made significant improvements. CT but not AP was associated
with significant reductions in medication usage, and patients receiving CT
were generally more positive about treatment received. Differences between
treatments were less evident in the less intensive treatment condition where
overall results were relatively poor. The most positive outcomes were
achieved in the more intensive CT condition in which approximately two-thirds of patients achieved clinically significant improvements.
The naturally occurring weevil (Curculionidae) fauna of Dade and Monroe counties in southern Florida is composed of 100 genera and 222 species. Another 20 species are adventive; their presence is due to the unintentional action of humans. Twenty-eight species occur only on the islands of the Florida Keys, 118 species occur only on mainland south Florida, and 76 species are shared by the mainland and the islands. Greater habitat diversity on the mainland accounts for its higher species diversity. The species distributions and faunal affinities are 60% Nearctic and 40% Neotropical or West Indian. Thirty-five species are known to occur only in southern Florida. This probably reflects poor knowledge of their distribution in the Caribbean rather than southern Florida as an important site for species origin. Most of the weevil species (133; 60%) are habitat specific and few species (22; 10%) are found in three or more habitat types. Wetland-inhabiting species are predominant (76; 34%), followed by hardwood hammock species (47; 21%). Flightlessness in adults is uncommon (35 species; 16%), but more prevalent in the species endemic to southern Florida (12 species; 34%). Extrapolation from data on weevil diversity yields a conservative estimate of over 5000 species of insects in southern Florida.
On western North Island, New Zealand, a record of climatic change during the last glaciation is preserved in a terrestrial coverbed sequence of dominantly andesitic provenance. Here, a succession of five loess-like Andisol units postdates the global high sea-level stand of oxygen isotope substage 5e (<125,000 yr). Tephra erupted from western and central North Island allow precise chronological correlation of the loess-like units. Aerosolic quartz additions determined by quantitative X-ray diffraction (XRD) record two major peaks that correlate with oxygen isotope stages 2 and 4. The most likely source of quartz-rich dust at these times is the surrounding continental shelf, then exposed by low sea level; however, quartz of Australian provenance may also be represented. This study provides the first confirmation from the terrestrial New Zealand record that rates of atmospherically transported particles increase during glacial stages.
Four vitamin B12 assays were compared using blood sera from Friesian cows on winter diets or grazing. In herd 1, ten animals were blood-sampled three times at monthly intervals and the vitamin B12 concentration of the sera determined by the Poteriochromonas malhamensis and Lactobacillus delbrueckii assays. At all three sampling dates the results produced by the P. malhamensis assay were significantly greater than those produced by the L. delbrueckii assay. Cows in herd 2 were divided into two groups, each of 30 animals. One group was given a soluble glass bolus releasing cobalt and the other was unsupplemented. Milk yields were recorded throughout the experimental period and herbage samples were taken at intervals for cobalt determinations. Blood samples were taken at intervals from January to September 1983 and the vitamin B12 concentration of the sera determined by four different assay methods: the P. malhamensis and L. delbrueckii microbiological assays and the Becton Dickinson and RIA Products ‘No-boil’ radioassays. The last of these failed to detect vitamin B12 in any sample. There was a significant difference between the results obtained by the three other assays, with the Becton Dickinson radioassay consistently producing the lowest result and the P. malhamensis assay the highest result of the three. There was no significant effect of cobalt supplementation on milk yield.