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1.
ANDREA S. WILEY 《American anthropologist》2007,109(4):666-677
Large-scale milk production and consumption historically have been localized to Europe and countries with large European-derived populations. However, global patterns have now shifted, with dramatic increases in milk consumption in Asian countries and flat or declining consumption in European and European-derived countries. Efforts to market it around the world emphasize milk's positive effects on child growth, and, by extension, the individual and national benefits that derive from that growth. At the same time, milk has newly emerged in milk promotions in the United States as food that facilitates weight loss. Milk has been able to achieve a global presence and continuing relevance in populations in which its consumption has been declining by continually transforming and repositioning itself as a "special" food with properties able to alleviate the health concerns seen as most salient at the time. 相似文献
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MICHAEL WILEY STEVEN KOHLER & PAUL SEELBACH 《The Plant journal : for cell and molecular biology》2004,37(1):133-148
1. Rapidly advancing geographical information systems (GIS) technologies are forcing a careful evaluation of the roles and biases of landscape and traditional site-based perspectives on assessments of aquatic communities. Viewing the world at very different scales can lead to seeming contradictions about the nature of specific ecological systems. In the case of Michigan trout streams, landscape analyses suggest a predictable community shaped by large-scale patterns in hydrology and geology. Most site-based studies, however, suggest these communities are highly variable in structure over time, and are strongly shaped by site-specific physical and biological dynamics. As the real world is comprised of processes operating both at local and landscape scales, an analytical framework for integrating these paradigms is desirable.
2. Decomposition of variances by factorial ANOVA into time, space and time–space interaction terms can provide a conceptual and analytical model for integrating processes operating at landscape and local scales. Using this approach, long-term data sets were examined for three insects and two fishes common in Michigan trout streams. Each taxon had a unique variance structure, and the observed variance structure was highly dependent upon sample size.
3. Both spatially extensive designs with little sampling over time (typical of many GIS studies) and temporally extensive designs with little or no spatial sampling (typical of population and community studies), are biased in terms of their view of the relative importance of local and landscape factors. The necessary, but in many cases costly, solution is to develop and analyse data sets that are both spatially and temporally extensive. 相似文献
2. Decomposition of variances by factorial ANOVA into time, space and time–space interaction terms can provide a conceptual and analytical model for integrating processes operating at landscape and local scales. Using this approach, long-term data sets were examined for three insects and two fishes common in Michigan trout streams. Each taxon had a unique variance structure, and the observed variance structure was highly dependent upon sample size.
3. Both spatially extensive designs with little sampling over time (typical of many GIS studies) and temporally extensive designs with little or no spatial sampling (typical of population and community studies), are biased in terms of their view of the relative importance of local and landscape factors. The necessary, but in many cases costly, solution is to develop and analyse data sets that are both spatially and temporally extensive. 相似文献
3.
E. O. WILEY 《Zoological Journal of the Linnean Society》1979,67(2):149-179
The ventral gill arch muscles of chondrichthyans, Latimeria , dipnoans, larval amphibians and actinopterygians are described and compared. Muscle patterns are characterized as primitive or derived and the derived patterns are used to test various hypotheses of the interrelationships of these griathostome groups. Gnathostomes differ from agnathans in having branchial muscles associated with the ventral gill arches. The monophyly of chondrichthyans is corroborated by the presence of coracobranchiales of hypobranchial origin. The monophyly of Recent teleostomes (Osteichthyes) is indicated by the presence of discrete transversi ventrales and interarcuales ventrales, and by the loss of the fifth superficial constrictor. A monophyletic Sarcopterygii which includes Latimeria is refuted by three paired branchial muscles found in dipnoans, Recent choanates and actinopterygians, but missing in Latimeria: pharyngoclaviculares, obliqui ventrales 1 and transversi ventrales 4. A new name, Euosteichthyes, is proposed for the group including dipnoans, choanates and actinopterygians. Sarcopterygii is restricted to include only dipnoans and choanates (among Recent organisms). Actinistia, including Latimeria , is proposed as the sister-group of all other Recent osteictithyans. Brachiopterygians (polypterids) are placed within Actinopterygii. A phylogenetic hypothesis supporting this classification is presented. 相似文献
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5.
WILEY M. KITCHENS 《Ibis》2012,154(3):554-565
The degradation of habitats due to human activities is a major topic of interest for the conservation and management of wild populations. There is growing evidence that the Florida Everglades ecosystem continues to suffer from habitat degradation. After a period of recovery in the 1990s, the Snail Kite Rostrhamus sociabilis population suffered a substantial decline in 2001 and has not recovered since. Habitat degradation has been suggested as one of the primary reasons for this lack of recovery. As a consequence of the continued degradation of the Everglades, we hypothesized that this would have led to increased movement of juvenile Kites over time, as a consequence of the need to find more favourable habitat. We used multistate mark‐recapture models to compare between‐site movement probabilities of juvenile Snail Kites in the 1990s (1992–95; which corresponds to the period before the decline) and 2000s (2003–06; after the decline). Our analyses were based on an extensive radiotelemetry study (266 birds tracked monthly over the entire state of Florida for a total period of 6 years) and considered factors such as sex and age of marked individuals. There was evidence of increased movement of juvenile Snail Kites during the post‐decline period from most of the wetland regions used historically by Kites. Higher movement rates may contribute to an increase in the probability of mortality of young individuals and could contribute to the observed declines. 相似文献
6.
Reconciling landscape and local views of aquatic communities: lessons from Michigan trout streams 总被引:10,自引:0,他引:10
1. Rapidly advancing geographical information systems (GIS) technologies are forcing a careful evaluation of the roles and biases of landscape and traditional site-based perspectives on assessments of aquatic communities. Viewing the world at very different scales can lead to seeming contradictions about the nature of specific ecological systems. In the case of Michigan trout streams, landscape analyses suggest a predictable community shaped by large-scale patterns in hydrology and geology. Most site-based studies, however, suggest these communities are highly variable in structure over time, and are strongly shaped by site-specific physical and biological dynamics. As the real world is comprised of processes operating both at local and landscape scales, an analytical framework for integrating these paradigms is desirable.
2. Decomposition of variances by factorial ANOVA into time, space and time–space interaction terms can provide a conceptual and analytical model for integrating processes operating at landscape and local scales. Using this approach, long-term data sets were examined for three insects and two fishes common in Michigan trout streams. Each taxon had a unique variance structure, and the observed variance structure was highly dependent upon sample size.
3. Both spatially extensive designs with little sampling over time (typical of many GIS studies) and temporally extensive designs with little or no spatial sampling (typical of population and community studies), are biased in terms of their view of the relative importance of local and landscape factors. The necessary, but in many cases costly, solution is to develop and analyse data sets that are both spatially and temporally extensive. 相似文献
2. Decomposition of variances by factorial ANOVA into time, space and time–space interaction terms can provide a conceptual and analytical model for integrating processes operating at landscape and local scales. Using this approach, long-term data sets were examined for three insects and two fishes common in Michigan trout streams. Each taxon had a unique variance structure, and the observed variance structure was highly dependent upon sample size.
3. Both spatially extensive designs with little sampling over time (typical of many GIS studies) and temporally extensive designs with little or no spatial sampling (typical of population and community studies), are biased in terms of their view of the relative importance of local and landscape factors. The necessary, but in many cases costly, solution is to develop and analyse data sets that are both spatially and temporally extensive. 相似文献
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ANDREA S. WILEY 《American anthropologist》2004,106(3):506-517
Cow's milk is accorded a high cultural value in the contemporary United States. Its white color, association with the maternal and the pastoral, and repeated mention in the Bible add positive symbolic weight to this major national agricultural commodity. Thus, it comes as no surprise that influential policy-making institutions in the United States recommend milk consumption for all U.S. groups. This is despite variation in adult populations' abilities to digest milk, which has been documented by biological anthropologists. This article assesses various U.S. "stories" about milk consumption and its relationship to biological variation against the biological anthropological explanation of variation in lactase activity/lactose tolerance. Many of these serve as normalizing discourses that ultimately pathologize biological difference and may undermine the dietary traditions of some ethnic groups. In particular, the close relationship between government and the dairy industry leads to policies that fail to seriously consider variation in digestive physiology among the diverse U.S. populations. 相似文献
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JAY A. LEVY PAUL ARNSTEIN ELLEN R. DIRKSEN MARVIN SIPERSTEIN MILLIE WILEY 《Differentiation; research in biological diversity》1982,22(1-3):12-18
An epithelial cell line, 3105, with an unusual growth pattern has been derived from the liver of an (NZBxNZW)F1 mouse. When confluent, it forms a monolayer of closely packed cells interspersed with holes that do not fill in during cultivation. By electron microscopy, the line has tight and intermediate junctions as well as desmosomes typical of epithelial cells. It produces several enzymes normally present in liver including hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase, glucose-6 phosphatase, and alkaline phosphatase; has cytochromes P-450 and b5 ; and spontaneously releases xenotropic but not ecotropic endogenous mouse type C viruses. Inoculation of the cell line into athymic nude mice gives rise to benign cysts in 2–3 months. This mouse epithelial line with hepatocyte characteristics should be helpful to investigators as a cell model of normal liver cell differentiation. 相似文献