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The mammalian assemblage and archaeological finds from the Lower Palaeolithic hominid site of Evron Quarry, situated on the northern coastal plain of Israel, are described and discussed. In their lithic and faunal composition, the sites of Latamne (QfIII) (Latamne Formation, Orontes, Syria) and Sitt Markho (Nahr elKebir, Syria) resemble Evron and are probably contemporaneous. It is suggested here, based on their lithic and faunal composition, that these sites may be chronologically closer to the site of Ubeidiya ('Ubeidiya Formation, Jordan Valley, Israel; 1.4 myr) than to the sites of Gesher Benot Ya'akov (dated as <800,000 yr B.P.), which differs in both aspects from Evron. The mammalian faunule from Evron comprises a biogeographical mixture, a result of biotic exchanges with Africa, the Oriental region, and the Palaearctic. This exchange may have been associated with a post-'Ubeidiya hominid dispersal, either from Africa or south Asia via the Levantine "corridor."  相似文献   
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Climate is a major determinant of energy demand. Changes in climate may alter energy demand as well as energy demand patterns. This study investigates the implications of climate change for energy demand under the hypothesis that impacts are scale dependent due to region-specific climatic variables, infrastructure, socioeconomic, and energy use profiles. In this analysis we explore regional energy demand responses to climate change by assessing temperature-sensitive energy demand in the Commonwealth of Massachusetts. The study employs a two-step estimation and modeling procedure. The first step evaluates the historic temperature sensitivity of residential and commercial demand for electricity and heating fuels, using a degree-day methodology. We find that when controlling for socioeconomic factors, degree-day variables have significant explanatory power in describing historic changes in residential and commercial energy demands. In the second step, we assess potential future energy demand responses to scenarios of climate change. Model results are based on alternative climate scenarios that were specifically derived for the region on the basis of local climatological data, coupled with regional information from available global climate models. We find notable changes with respect to overall energy consumption by, and energy mix of the residential and commercial sectors in the region. On the basis of our findings, we identify several methodological issues relevant to the development of climate change impact assessments of energy demand.  相似文献   
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Recent satellite observations of thermal ion composition in the near-equatorial plasmasphere have shown that He+ comprises 5–10% typically and occasionally 25% or more of the total thermal ion density. A steady state diffusive equilibrium model for the distributions of H+, He+ and O+ along a plasmaspheric flux tube is used to elicit effects that may help explain these observed high He+ fractional concentrations. The model indicates that both the ionospheric composition and the temperature distribution along the flux tubes are important factors controlling the equatorial He+ composition, through the plasma scale height and thermal diffusion effects. Direct comparison of the model results with thermal ion observations by ISEE-1 indicates that the effects incorporated into the model may explain some of the elevated He+ concentrations. In some instances, however, effects not included in the model may also be of importance.  相似文献   
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Palinspastic profiles across the Paraburdoo Hinge Zone, which forms the southwestern boundary to the Hamersley Shelf, indicate the existence of a fore-trough, adjacent to the Ashburton Trough, on the edge of the Hamersley Shelf. The fore-trough existed during Turee Creek Group and Lower Wyloo Group times of deposition and is characterized by unconformities or shallow-water facies on its margins. The distribution of mature iron-ores in the Hamersley Group suggests a relationship of this type of ore-body to the fore-trough margins.Continual uplift, or a gradual migration northeastwards of a geanticline, is suggested for the Ashburton Trough region from post-Hamersley Group times to pre-Ashburton Formation times of deposition.  相似文献   
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An age of 3112 ± 6 (2σ) Ma, determined by conventional techniques on single zircons from a felsic volcanic rock from the Sholl Belt in the western part of the Archaean Pilbara Craton of Western Australia, is interpreted as the age of felsic volcanism. This is about 100 Ma older than felsic volcanic rocks in the nearby but unconnected Whim Creek Belt and is significantly younger than felsic volcanism in the East Pilbara, which took place during two distinct episodes at 3450 Ma and 3300 Ma. The present results rule out previous correlations between the felsic volcanic rocks of the Sholt Belt and the 3452 ± 16 Ma old Duffer Formation in the East Pilbara.  相似文献   
7.
Liora Bigon 《GeoJournal》2014,79(1):103-111
The organisation, guiding rationale and the conclusions of the conference on yellow fever that was held in Dakar in April 1928 provide us an insight on how inter-colonial networks for administrating disease and urban planning in sub-Saharan Africa operated. During the period of ‘empire building’ national rivalries were strengthened but at the same time there emerged international and inter-colonial coordination. This contemporary cooperation-cum-competition is well reflected in the Dakar conference, throwing some light on the meaning and implications of such transnational networks of scientific expertise. Against this background another issue will be discussed, residential segregation on a racial basis in British and French sub-Saharan Africa.  相似文献   
8.
Santa Rosa Island is an 85 km-long, wave-dominated low-lying barrier island situated along the northwestern Florida coast, facing the Gulf of Mexico. The entire island was severely impacted by Ivan, a strong category 3 hurricane that made landfall about 45 km to the west in September of 2004. Ten months later in July of 2005, Dennis, another category 3 hurricane, made landfall about 30 km east of the western tip of the island. Santa Rosa Island is characterized by well-developed but relatively low dunefields, described in this paper as incipient and established dunes, based on the presence of grassy and woody types of vegetation, respectively. The dunes were severely eroded by the two hurricanes. This paper investigates the factors controlling the regional-scale destruction and survival of the dunefields.Dune survival is controlled by: 1) hurricane characteristics, including intensity, duration, and frequency, and 2) morphological parameters including width of the barrier island, height and width of the dunefields, vegetation type, distance of the dunes to the ocean, and continuity of the dunefields. Three processes of dune destruction are described including, from most to least severe, inundation, overwash, and scarping. The interaction of all the above factors determines the different dune responses to the storm impacts. In general, the extensive and densely woody vegetated dunefields near the bay-side shoreline survived the storms, while the discontinuous dunes with grassy vegetation near the Gulf shoreline were almost completely destroyed.  相似文献   
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Electrochemically controlled pyrite dissolution was performed with three pyrite materials from different geological origins under mixed potential and high overpotential conditions. Both solid electrodes and C paste electrodes of powdered pyrite were used. The rate of pyrite dissolution increased with applied positive potential and was strongly affected by temperature. Current density measurements over the applied potential range successfully described the rate of pyrite dissolution of each pyrite electrode. Controlled dissolution performed under mixed potential conditions on the solid electrodes successfully reflected the same pyrite reactivity and dissolution rate order as in batch reactor dissolution studies with the same pyrite materials. Therefore, the relative reactivity of different pyrite materials can be determined through current density measurements on their solid electrodes under mixed potential conditions. This technique could be a useful tool to compare rapidly the relative reactivity for different pyrite materials. In contrast, electrochemically controlled dissolution studies with C paste electrodes constructed with fine-grained pyrite and paraffin/graphite mixture did not result in accurate ranking of pyrite samples by dissolution rate.  相似文献   
10.
The Hudson River estuary has enormous spatial variation in polychlorinated biphenyl (PCB) contamination due in large part to historical point source discharges above Troy Dam. The Delaware River estuary has accumulated significant levels of PCBs through decades of industrial, municipal, and non-point source inputs. The overall goal of this research was to use existing data sets to compare and contrast the patterns of accumulated PCB congeners in sub-populations of American eels and striped bass inhabiting these two estuaries and surrounding coastal waters. Using principal component analysis and analysis of covariance (ANCOVA), inter- and intra-estuarine differences in accumulated congeneric patterns were denoted for both species. Results from our study support the idea that migratory behaviors of striped bass hamper the use of accumulated congener-specific PCB patterns in providing information on localized contamination, although major regional differences were seen between upriver Hudson River fish, downriver Hudson River fish and fish from other areas within this study. This study provides additional evidence for the use of the American eel as a biomonitoring tool, since its limited home range provides finer resolution of regional contamination.  相似文献   
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