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31.
This paper presents the results of a project aimed at investigating the deterioration of organic remains at the Mesolithic site of Star Carr. Analyses of pH, Electrical Conductivity and Redox Potential are reported from borehole transects across the unexcavated part of the site. A comparison of field and laboratory measurements is made, leading to the characterisation of different preservation zones and identification of ‘vulnerable’ sediments at the site. These data are augmented by geochemical analyses of contemporary borehole sequences and adjacent historic monoliths. Analysis of surface water and groundwater has also been undertaken to assist in the interpretation of the site hydrology and geochemistry. The relationship between ‘natural’ geology and preservation potential, and the evidence for a ‘halo’ preservation effect in virgin sediments adjacent to previous archaeology trenches is investigated.  相似文献   
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Previous theoretical and empirical work suggests differences in the way the congressional chambers approach the responsibility of agent control. The Senate should, the literature hypothesizes, exercise greater and qualitatively more systematic, substantive, and preemptive oversight of agents than does the House. Yet little research on congressional oversight has focused upon bicameral differences in principal behavior. This paper begins to fill the void by examining House and Senate oversight of the Federal Reserve. Specifically, I look at three types of oversight activity: monitoring of, and signaling to, the agent, and the principal's alteration of its contract with the agent. Utilizing original data and a variety of statistical methods, I show that there exist few, if any, quantitative and qualitative differences in House and Senate behavior. I then discuss theoretical reasons for my unexpected findings.  相似文献   
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The New Propaganda boom; Philip M. Taylor  相似文献   
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This study provides a unique method of inquiry for archaeological investigation with an aim to assess the intensity and effects of Neolithic and Bronze Age farming practices at Lough Dargan, northwest Ireland, through a multi-proxy analysis of a lake sediment core. Chironomid (non-biting midge fly) subfossils and lake sediment geochemistry (δ13C, δ15N and C:N ratios) were used to assess changes in limnological conditions through time. The limnological data were compared with macroscopic charcoal concentration and pollen data to examine the potential influence that early farmers had on a freshwater lake system within a prehistorically active catchment. Results from the chironomid analysis show that the first substantial period of agricultural activity in the early Neolithic (c. 3730–3190 BC) resulted in a temporary shift to more eutrophic lake conditions. There is evidence of animal husbandry with substantial levels of animal waste reaching the lake, leaving an imprint in the geochemical record of increased δ15N values and decreased δ13C values and C:N ratios during this time. The chironomid community reverted back to its pre-impacted state c. 3190 BC in response to a period of reduced farming (c. 3390–3000 BC) which eventually led to a distinct lull in activity, with possible cessation of farming from 3000 to 2700 BC. A return to eutrophic conditions coincided with the gradual return of agriculture, with more permanently altered lake conditions dominating from 2400 BC, even during a 250-year period of reduced human activity commencing at c. 1440 BC. Increased sedimentation rate, along with increases in δ13C, δ15N and C:N, the presence of chironomid taxa indicative of erosion, more eutrophic lake conditions and high concentrations of macroscopic charcoal all point to more intensive land use practices during the Bronze Age. Palaeolimnological data exhibited an immediate response to intensified farming during this time, and were especially responsive to pastoral farming due either to scale of activity or proximity to the lakeside. The success of this study demonstrates the effectiveness of palaeolimnological analysis in the investigation of prehistoric farming. This approach will help inform Neolithic and Bronze Age land-use practice and human–environment relations in the region, and highlights the potential for chironomid-based archaeological research.  相似文献   
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Marcusodictyon priscum (Bassler 1911) from the Tremadocian Ungulite Sandstone (A2) of Jegelecht Falls, Estonia, is redescribed following SEM study of type and other specimens. The fossil consists of a polygonal network of low ridges known to exist only on the exterior surfaces of valves of the inarticulate brachiopod Obolus. Electron microprobe analysis demonstrates that, like its host substratum, Marcusodictyon is composed of calcium phosphate. This, together with the detailed morphology and dimensions of the ridge system, is used to negate Bassler's assignment of the genus to the ctenostome Bryozoa. Instead Marcusodictyon resembles the Silurian problematicum Gochtia Eisenack. The inferred growth pattern of Marcusodictyon suggests that it may have been a symbiont of a living brachiopod.  相似文献   
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