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991.
Biogeographical studies are often based on a statistical analysis of data sampled in a spatial context. However, in many cases standard analyses such as regression models violate the assumption of independently and identically distributed errors. In this article, we show that the theory of wavelets provides a method to remove autocorrelation in generalized linear models (GLMs). Autocorrelation can be described by smooth wavelet coefficients at small scales. Therefore, data can be decomposed into uncorrelated and correlated parts. Using an appropriate linear transformation, we are able to extend GLMs to autocorrelated data. We illustrate our new method, called the wavelet‐revised model (WRM), by applying it to multiple regression with response variables conforming to various distributions. Results are presented for simulated data and real biogeographical data (species counts of the plant genus Utricularia [bladderworts] in grid cells throughout Germany). The results of our WRM are compared with those of GLMs and models based on generalized estimating equations. We recommend WRMs, especially as a method that allows for spatial nonstationarity. The technique developed for lattice data is applicable without any prior knowledge of the real autocorrelation structure. 相似文献
992.
Friendships Moderate an Association Between a Dopamine Gene Variant and Political Ideology 总被引:1,自引:0,他引:1
Scholars in many fields have long noted the importance of social context in the development of political ideology. Recent work suggests that political ideology also has a heritable component, but no specific gene variant or combination of variants associated with political ideology have so far been identified. Here, we hypothesize that individuals with a genetic predisposition toward seeking out new experiences will tend to be more liberal, but only if they are embedded in a social context that provides them with multiple points of view. Using data from the National Longitudinal Study of Adolescent Health, we test this hypothesis by investigating an association between self-reported political ideology and the 7R variant of the dopamine receptor D4 gene (DRD4), which has previously been associated with novelty seeking. Among those with DRD4-7R, we find that the number of friendships a person has in adolescence is significantly associated with liberal political ideology. Among those without the gene variant, there is no association. This is the first study to elaborate a specific gene-environment interaction that contributes to ideological self-identification, and it highlights the importance of incorporating both nature and nurture into the study of political preferences. 相似文献
993.
994.
T. Douglas Price James H. Burton Robert J. Sharer Jane E. Buikstra Lori E. Wright Loa P. Traxler Katherine A. Miller 《Journal of Anthropological Archaeology》2010
Eight human interments were excavated in the 1990s beneath the Acropolis at the Classic Maya site of Copan in Honduras, which was the capital of a Maya kingdom from ca. AD 400 to 800. These human remains come from both royal tombs and less elaborate burials dating to the early part of this period and lie deep in the accumulated architectural layers of the Acropolis. We present a brief summary of the context, contents, and external links represented by these interments. Several lines of evidence point to connections between early Copan and Teotihuacan in the Central Highlands of Mexico, and Tikal in the central Maya lowlands of the Petén in Guatemala. 相似文献
995.
996.
997.
Archaeological monitoring of construction in a Windsor city park on the Detroit River led to the discovery of an isolated cemetery containing the remains of eight individuals assigned to the Late Woodland Western Basin Tradition. At the request and consent of the contemporary First Nation community, tissue samples from five individuals were subjected to radiocarbon dating, mtDNA, and stable isotope analysis to confirm cultural affiliation and further understand the subsistence practices of these people. Radiocarbon dating placed the cemetery at the transition from the Younge phase (AD 900–1200) to the Springwells phase (AD 1200–1400). The stable carbon and nitrogen isotope results provide an unexpected but fuller understanding of Late Woodland Western Basin Tradition subsistence. All individuals were as enriched in carbon as those found on Iroquoian horticulturalist sites to the east, suggesting a very high reliance on maize. Nitrogen isotope values indicate that the protein component of the diet was comprised largely of high trophic level food sources, likely fish. An in situ osteological analysis identified a high number of carious lesions in the visible teeth, also suggesting a diet high in carbohydrates. The mtDNA findings support the antiquity of the Western Basin presence in Northeast North America through genetic links with the Hind Site, an Archaic site in southern Ontario. These results underscore the importance of such studies for providing novel insight into the archaeological histories and lifeways of this distinct Late Woodland tradition. This study also emphazises the need to work with descendant communities to provide them with information on the past that reflects their distinct heritage in the lower Great Lakes region. 相似文献
998.
Sila Tripati Abhay MudholkarK.H. Vora B. Ramalingeswara RaoA.S. Gaur Sundaresh 《Journal of archaeological science》2010
Stone anchors have been recovered along the Indian coast as a part of the maritime archaeological studies at the National Institute of Oceanography (NIO), Goa. Study of stone anchors provides clues to understand the ancient maritime trade contacts of India with other countries. These anchors resemble those found in the Mediterranean Sea, Persian Gulf and Red Sea Coast. Underwater explorations at Bet Dwarka, Dwarka, Goa, Visawada and Somnath have yielded stone anchors of widely varying shapes, sizes and weights ranging between 16 and 410 kg. Sixteen (10 Indo-Arabian, 4 Ringstone and 2 Single hole type) of the total of 269 stone anchors have been studied to determine provenance of rock through petrographic analysis using thin section studies, X-ray Fluorescence (XRF), and Scanning Electron Microscope – Energy Dispersive Spectrometer (SEM-EDS). 相似文献
999.
1000.
Geographical development economics as reflected in the recent report by World Bank (2009) Reshaping Economic Geography (henceforth WDR-2009) and Sachs' (2005) End of Poverty has placed geographical factors of distance and density at the core of economic development. However, development geography has largely moved beyond a paradigm of modernity. This article seeks to narrow the above disciplinary divide and suggests that explanations of distance and density are not irrelevant but will need to be better integrated to local knowledge, practices and power relations in development schemes which are valued by development geographers. The latter is examined in the context of micro-credit programmes in two lagging areas, Soc Son and Vinh Loc, in northern Vietnam. Drawing from interviews and surveys of 160 female participants, we show that micro-credit, WDR-2009 and Sachs' geographical variables significantly affect poverty levels. However, qualitative interviews also reveal that the effects of distance, density and micro-credit schemes are constituted differently in the two areas. Relative to their Vinh Loc counterparts, Soc Son's participants experience less distance and density problems but are confronted with greater vulnerability to coercive relations of rule. In contrast, the approach to rule in the more geographically distressed area of Vinh Loc is underscored by flexibility and compromise which seek to cultivate conditions that sustain local livelihoods. 相似文献