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Chronic wasting disease (CWD) has become a major concern among those involved in managing wild and captive cervid populations. CWD is a fatal, highly transmissible spongiform encephalopathy caused by an abnormally folded protein, called a prion. Prions are present in a number of tissues, including feces and urine in CWD infected animals, suggesting multiple modes of transmission, including animal-to-animal, environmental, and by fomite. CWD management is complicated by the lack of practical, non-invasive, live-animal screening tests. Recently, there has been a focus on how the volatile odors of feces and urine can be used to discriminate between infected and noninfected animals in several different species. Such a tool may prove useful in identifying potentially infected live animals, carcasses, urine, feces, and contaminated environments. Toward this goal, dogs were trained to detect and discriminate CWD infected individuals from non-infected deer in a laboratory setting. Dogs were tested with novel panels of fecal samples demonstrating the dogs' ability to generalize a learned odor profile to novel odor samples based on infection status. Additionally, dogs were transitioned from alerting to fecal samples to an odor profile that consisted of CWD infection status with a different odor background using different sections of gastrointestinal tracts. These results indicated that canine biodetectors can discriminate the specific odors emitted from the feces of non-infected versus CWD infected white-tailed deer as well as generalizing the learned response to other tissues collected from infected individuals. These findings suggest that the health status of wild and farmed cervids can be evaluated non-invasively for CWD infection via monitoring of volatile metabolites thereby providing an effective tool for rapid CWD surveillance. [ABSTRACT FROM AUTHOR]

The author wishes to thank Barry Bull for his excellent and stimulating paper, and he would like to pose five questions or points for his consideration in response. In preface to his first question, the author wants to say that he finds cogent and persuasive the discussion in the section "Issues for Political Liberalism in Higher Education" of reasons for a politically liberal society to take responsibility for higher education. He suggests that all of these "reasons" have to do with the "instrumental value," as Professor Bull says at one point, of education for politically liberal society. In other words, all these "reasons" explain ways in which education fosters political liberalism and prepares citizens for political liberalism. He makes this point because the term "reasons" and other wording in these pages and in the opening paragraphs of the section on "Political Liberalism and Children's Education" suggest that education, in its nature, is especially suited or important to politically liberal society. However, to make that argument would require a large discussion about the nature of education. The author's second question concerns the relationship between Rawls's views of justice as fairness and the politically liberal society. His third question concerns the relationship between empirical and normative claims in the essay, as well as the relationship between American society and political liberalism. His fourth question concerns what might be called the conceptual status of the four points that are presented in the essay and the accompanying table. His fifth and final question concerns the balance between personal and social considerations in formulating principles and policies that are politically liberal. (Contains 1 footnote.)

Many serious ecosystem consequences of climate change will take decades or even centuries to emerge. Long-term ecological responses to global change are strongly regulated by slow processes, such as changes in species composition, carbon dynamics in soil and by long-lived plants, and accumulation of nutrient capitals. Understanding and predicting these processes require experiments on decadal time scales. But decadal experiments by themselves may not be adequate because many of the slow processes have characteristic time scales much longer than experiments can be maintained. This article promotes a coordinated approach that combines long-term, large-scale global change experiments with process studies and modeling. Long-term global change manipulative experiments, especially in high-priority ecosystems such as tropical forests and high-latitude regions, are essential to maximize information gain concerning future states of the earth system. The long-term experiments should be conducted in tandem with complementary process studies, such as those using model ecosystems, species replacements, laboratory incubations, isotope tracers, and greenhouse facilities. Models are essential to assimilate data from long-term experiments and process studies together with information from long-term observations, surveys, and space-for-time studies along environmental and biological gradients. Future research programs with coordinated long-term experiments, process studies, and modeling have the potential to be the most effective strategy to gain the best information on long-term ecosystem dynamics in response to global change.

The mountain beaver is a semi-fossorial rodent of the Pacific Northwest and is among a variety of herbivores that retard plant growth and cause tree seedling deformities and mortality. Douglas-fir seedlings are planted in the Pacific Northwest from February through March, a period coinciding with mountain beaver parturition. Previous research suggested that in spring, lactating females depend more on conifers than do non-lactating females and males. We conducted experiments to determine if female reproductive condition influenced seedling damage, and if physiological stage of the seedling affected damage. Dormant and flushing trees were offered to 6 pregnant and 6 non-pregnant females in 2002 and 2003. We found no difference between female condition and damage in 2002, but there was a significant difference between type of tree and damage (F6,79 = 6.75, P < 0.001). In 2003, we found a difference in seedling damage (F3,95 = 16.41, P < 0.001), with tree type (P < 0.001) and female condition (P = 0.02) contributing to the model. More flushing trees were damaged in both years than dormant trees, once bud break occurred. Statistical analyses of fructose (F5,23 = 12.07, P < 0.001) and glucose (F5,23 = 12.86, P < 0.001) concentration data indicate that tree type (dormant or flushing) was a significant effect (P < 0.001). The interaction between tree type and week sampled was also significant in both the glucose (P = 0.002) and fructose response (P = 0.009). Both fructose and glucose concentrations were the lowest in new flushing trees, and mountain beaver did not appear to be selecting flushing trees for their needle sugar content. Water concentration also varied between tree type but was not affected by the sampling time (F5,20 = 35.46, P < 0.001). New and dormant growth tissues had similar water concentrations that were greater than old growth tissue. Mountain beaver are dependent upon a constant water source, although it does not appear that damage is related to water availability. Further analyses of terpene levels and stem carbohydrate levels are needed before conclusions on mountain beaver selectivity can be reached.

Deer foraging on tree seedlings is recognized as the most widespread detriment to reforestation efforts. Non-lethal approaches to reduce deer damage to seedlings are highly desirable. Avoidance of natural secondary metabolites contained in conifers may provide feasible means to develop non-lethal measures. Other studies have demonstrated that sheep and goats fed diets with high protein-to-energy ratios, or allowed to select between concentrates high in either energy or protein, ate much more of a high-terpene diet and of a high-tannin diet than when they were fed diets high in energy-to-protein ratios. Thus, manipulating foraging options for deer may impact their ability to ingest terpenes contained in conifers. We conducted a series of studies to determine whether deer acceptance of terpene-containing foods can be affected by altering the ratio of energy and protein in their maintenance diet. We determined relative consumption of a high-energy and low-protein diet, and a low-energy and high-protein diet, when deer are given the opportunity to self-regulate their intake. We also determined if deer modified their relative intake of these diets when offered an alternative terpene-treated diet. Penned deer were offered variable diets (e.g., high energy-low protein, low-energy-high protein, or both foods), then their acceptance of terpene- and tannin-containing foods was determined. Deer consumed more and demonstrated a strong preference for the high-energy diet relative to the high-protein diet. However, the varied diets did not appear to affect their intake of terpene or tannin-containing foods. This paper discusses the potential of manipulating maintenance rations as a non-lethal tool, presents initial results and possible explanations for differences between our study with deer and prior work with domestic ruminants.

Coyote attractants are inherently variable because they are usually derived by mixing and fermenting complex biologically derived substances. We designed the present study to address this problem. We collected volatiles by purge and trap headspace analyses from 33 commercially available attractants, and analyzed the trapped odors by gas chromatography with mass selective detection. We then statistically evaluated chromatographic peak area data to produce recipes for seven new chemical attractants. We presented these attractants to coyotes in one-choice tests at the Predation Ecology and Behavioral Applications Field Station of the USDA-APHIS-WS National Wildlife Research Center near Logan, Utah. Our results indicated that there were both seasonal and sexual differences in stimulus attractiveness. We also found that several attractants were more effective than Fatty Acid Scent (FAS), a commonly employed coyote attractant. A field trial to evaluate the effectiveness of new candidate attractants is planned.

Cabergoline, a prolactin inhibitor, was evaluated on its potential use as a reproductive inhibitor for coyotes (Canis latrans). Groups consisting of six female coyotes were randomly assigned to three treatments and a control group. At 25 to 35 days after fertilization, coyotes were palpated to verify pregnancy status. If an animal was confirmed pregnant, it was dosed with 50 μg, 100 μg, or 250 μg of cabergoline, or a placebo for seven consecutive days on approximately day 40 days of gestation. Five animals dosed with 50 μg of cabergoline, three dosed with 100 μg, and three animals receiving placebo whelped; no animals treated with 250 μg whelped. No drop in serum progesterone or prolactin levels were observed for the 50 μg and 100 μg treated groups. However, progesterone levels declined below 2 ng/ml in animals treated with 250 μg. Prolactin and progesterone levels in the control group followed typical patterns observed in pregnant canines. This study suggests that cabergoline is a potential reproductive inhibitor in coyotes. Future studies should determine if the efficacy of cabergoline in terminating pregnancy in coyotes could be improved with higher doses and at earlier stages of gestation.

Black bears forage on Douglas-fir vascular tissue in the spring, and this behavior can be severely detrimental to the health and economic value of a timber stand. Foraging is selective in that not all stands are damaged and, within a stand, one tree may be stripped while its neighbor is ignored or minimally sampled. A series of studies was conducted to assess whether bear selectivity is affected by chemical constituents within vascular tissue, and whether these constituents are affected by silvicultural practices. The results are interpreted to identify forest practices that may alleviate damage, or at least predict where damage is most likely to occur.

Case method teaching was first introduced into American higher education in 1870 by Christopher C. Langdell (1826-1906) of Harvard Law School (HLS), where it became closely associated with a complex of academic meritocratic reforms. "Mr. Langdell's method" became, in fact, emblematic, "creating and embodying cultural values and messages" of the HLS reforms. Generally dismissed as an "abomination," case method and the associated reforms were largely confined to Harvard for the next two decades. The ensuing determinative period between 1890 and 1915 then resolved the question as to whether case method teaching--and the concomitant, academic meritocratic reforms--would predominate in legal education and, ultimately, professional education in the United States. This essay analyzes the early proliferation of case method within legal education and attempts to identify and explain the means, the factions, and the reasons associated with the first step in the massive pedagogical shift toward case teaching that occurred in 20th century higher education. (Contains 6 tables, 1 figure and 177 footnotes.)

Presents an evidenced account of Christopher Columbus Langdell, arguably the best-known and most influential figure in the history of U.S. legal education, from his birth in 1826 until his departure from law school in 1854. Attempts to explain the formation of his interest in education, as well as the origins of significant reforms in legal education that he advanced as dean of Harvard Law School. (EV)