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Jennifer Porter David Conner Jane Kolodinsky Amy Trubek 《Agriculture and Human Values》2017,34(4):921-932
The Real Food Challenge is a national student movement in the United States (U.S.) that aims to shift $1 billion—roughly 20%—of college and university food budgets across the country towards local, ecologically sound, fair, and humane food sources—what they call “real” food—by 2020. The University of Vermont (UVM) was the fifth university in the U.S. to sign the Real Food Campus Commitment, pledging to shift at least 20% of its own food budget towards “real” food by 2020. In order to examine student preference for “real” food on the UVM campus, we analyzed a survey of 904 undergraduate students that used contingent valuation to evaluate students’ willingness-to-pay (WTP) for the “real” attribute. We found that a majority of students are willing to pay a positive premium for “real” food. Furthermore, we found that student characteristics and attitudes significantly influence WTP. Specifically, gender, residency, college, and attitudes about price and origin of food are significant predictors of WTP. 相似文献
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We examined the response of bird communities to a gradient of human impact in the Adirondack Park of northern New York State by testing the relationship of land use management types to an Index of Biotic Integrity (IBI) across the Adirondack landscape. We created the IBI by placing birds into 12 different guild categories and scoring study blocks according to relative representation of specialist versus generalist guild types. We investigated three questions relating to the effects of land use management on biotic integrity in the Adirondacks: (1) are there differences in biological integrity among the major land use types; (2) if so, what characteristics of these land use types are associated with high integrity bird communities; and, (3) to what degree is land management regulation effective in maintaining biological integrity in the Adirondack Park? We found significant differences in total, functional, compositional, and structural integrity on five land use types ranging from hamlet to wilderness. In all cases, integrity was lowest in hamlet areas and increased along the gradient to its highest level in wilderness areas.Biotic integrity showed strong groupings of the five land use classes. We found that bird community integrity was strongly related to roadlessness and that birds primarily responded to the distinction between developed and undeveloped land types. In contrast to roads and human development, forest management impacts in the Adirondacks do not appear to be of a high enough intensity to have significant negative impacts on breeding bird community integrity. Clustering of development is a means by which integrity may be safeguarded for the long term in the Adirondack Park. 相似文献
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Changes in ovine visceral organ mass and small intestinal mucosa morphology and metabolism due to short-term and prolonged modifications in level of alimentation were studied. Thirty-six lambs were fed for 21 d at either 100 or 50% ad libitum levels of intake. For the next 5 d, lambs either remained on the same intake levels or were switched from 100 or 50% or from 50 to 100% ad libitum intake levels and were subsequently slaughtered. Levels of alimentation the last 5 d before slaughter had a significant effect on weights of the large intestine, small intestine, stomach complex and liver, while only the weight of the liver was affected by 21-d adaptation period. Weights of the heart, lungs, carcass and visceral fat were not affected by level of alimentation. Villus height and mucosal mass at a constant intestinal tissue weight were modified by level of alimentation 5 d before slaughter but static to the previous 21-d nutritional plane. Activity of Na+, K+ ATPase of jejunal mucosa was not influenced by level of alimentation 5 d before slaughter, but was influenced by 21-d adapted level of alimentation. Results from this study are interpreted to indicate that weights of the liver and alimentary tract and small intestinal mucosa development are highly sensitive to changes in level of alimentation. 相似文献
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Short-chain fructooligosaccharides (FOS) were supplemented to the diets of nine quarter horses ranging in age from 489 to 539 d with initial BW averaging 400.6 +/- 21.2 kg. The objectives of this study were to determine the effects of dietary FOS on the fecal responses in terms of pH, the microbial population, and VFA concentrations. The horses were used in a 3 x 3 replicated Latin square design, fed according to NRC requirements, and their individual diets were supplemented with no FOS (CON), 8 g of FOS/d (LOW), or 24 g of FOS/d (HIGH) over three 10-d feeding periods. On the last 3 d of each 10-d feeding period, a single fecal sample was collected between 0730 and 0930. Fecal pH decreased linearly (P = 0.01) from 6.48 with the CON diet to 6.38 with the HIGH diet, but there was no change (P = 0.19 for linear effect) in fecal consistency among treatments. A quadratic effect (P < 0.01) was observed for fecal Escherichia coli population, but no difference (P = 0.88 for linear effect) was found in fecal Lactobacilli enumeration among treatments. The presence of fecal Bifidobacteria was unable to be confirmed and was therefore not reported. Fecal acetate concentrations increased linearly (P = 0.03), with means of 2.13, 2.18, and 2.52 mg/g of wet feces for CON, LOW, and HIGH treatments, respectively. Similarly, fecal propionate concentrations increased linearly (P = 0.01), with means of 0.58, 0.64, and 0.73 mg/g for CON, LOW, and HIGH treatments, respectively. Fecal butyrate concentrations also increased linearly (P = 0.02), with means of 0.40, 0.46, and 0.54 mg/g for CON, LOW, and HIGH treatments, respectively. Total VFA (P = 0.01) and lactate (P = 0.02) concentrations increased linearly, with total VFA means of 3.47, 3.69, and 4.25 mg/g for CON, LOW, and HIGH treatments, respectively, and lactate means of 0.36, 0.41, and 0.47 mg/g for CON, LOW, and HIGH treatments, respectively. Supplementing FOS in diets fed to yearling horses altered fecal microbial populations, fecal VFA concentrations, and pH. 相似文献
440.
Glioblastoma multiforme is the most malignant astrocytic neoplasm and the most common brain neoplasm of humans. Spontaneous neoplasms of the brain are rare in nonhuman primates. This report describes three glioblastomas in adult captive-reared baboons. The animals exhibited a range of clinical signs, including depression, weight loss, weakness, and blindness. All three neoplasms were located in the cerebrum, with extension into the pons in one case. Histologically, the tumors were similar and were characterized by cellular pleomorphism, multinucleated cells, areas of necrosis, microvascular proliferation (glomeruloid bodies), and palisading of neoplastic cells around blood vessels and areas of necrosis. Two baboons exhibited gemistocytic differentiation, and in one baboon, the neoplastic cells were predominantly spindle shaped with a fascicular growth pattern. Immunohistochemical staining for glial fibrillary acidic protein, vimentin, and S-100 protein was positive, whereas immunostaining for synaptophysin and chromogranin A was negative. Positive staining for the cell proliferation marker Ki67 ranged from 8.2% to 13.9%. Terminal deoxynucleotidyl transferase mediated dVTPnick end labeling (TUNEL) staining ranged from 1.8% to 5.7%. These baboon glioblastomas share many features with those of humans. 相似文献