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In this paper we present the sedimentary features and the luminescence chronology for Nahal Mahanayeem Outlet (NMO), an archaeological open air site at the southern margin of the Hula Basin (Northern Jordan Rift Valley, Israel). The site is characterized by a lithic assemblage ascribed primarily to the Middle Paleolithic Mousterian tradition, and by an excellent preservation of floral and faunal remains.
Six geological units forming the stratigraphic sequence of the site were distinguished: (Unit 6) archaeologically sterile, light-colored limnic carbonates; (Unit 5) conglomerates of rounded basalt boulders and cobbles forming a hill-like topography; (Unit 4 and Unit 3) a sequence of similar dark silty sediments, attached to and overlaying the conglomerates, containing the archaeological horizons of the site; (Unit 2) a number of channels cutting into the top of Unit 3, filled with coarse sand and rounded basalt and limestone gravels of fluvial origin; and (Unit 1) a thin sand layer laid down by the present-day Jordan River covering another unconformity as a result of heavy machinery drainage operations in 1999.
The OSL age for Unit 6 yielded a minimum age older than 460 ka. Sedimentary features and the embedded fossils suggest that Unit 1 can be linked to the Early Pleistocene Gadot Chalk. Unit 5 represents a local geological feature and could be an indicator for a period of increased erosion with formation of coarse grained sediments. The archaeological horizons form the lower parts of Unit 4 and yielded OSL-ages between 55 and 65 ka, indicating an affiliation to the sediments called "Ashmura Formation" with an Upper Pleistocene age for the site. The channel fills of Unit 2 can be dated by the recovered artifacts. These range in age from the Upper Paleolithic (Aurignacian) to historic times. Unit 1 is recent.
The study of the complex NMO stratigraphy, combined with coherent OSL chronology, has enabled us to reconstruct parts of the geological history of the Hula Basin during the Late Pleistocene. It is this history that forms the background for the human migration and utilization of natural resources in the Upper Jordan Rift Valley. (C) 2013 Elsevier Ltd and INQUA. All rights reserved.
We present ostracod data from the Middle Palaeolithic open air site of Nahal Mahanayeem Outlet (NMO) at the southern edge of the Hula Basin, northern Israel.
Sediments of two Pleistocene water bodies are exposed at the site. The first one is an archaeologically sterile, light-colored limnic carbonate with an Early Pleistocene age. It contains an ostracod fauna assemblage dominated by Candona neglecta, Candonopsis kingsleii, and Pseudocandona sp., and, in minor abundances, Cypria ophtalmica, Cyprideis sp., Humphcypris sp., Fabaeformiscandona cf. fabaeformis and Ilyocypris sp. These sediments were deposited in a shallow, freshwater to oligohaline lake under stable conditions.
Sediments of the second water body are silty and dark-colored with a depositional age of 65 ka, belonging to the Late Pleistocene Ashmura Formation. The unit covers a geologically complex topography of tectonically uplifted limnic deposits and a hill-like gravel bar at the site. The most important archaeological layer is situated at its base, containing a lithic assemblage ascribed primarily to the Middle Palaeolithic Mousterian tradition and very well preserved flora and fauna. In the sediments from the archaeological layers, the brackish water ostracod Cyprideis torosa and the foraminifer Ammonia tepida could be identified. In sediments of the Ashmura Formation taken near the site, C. neglecta, Candona angulata, Ilyogpris sp., C kingsleii, Pseudocandona sp., C ophtalmica, Darwinula stevensoni, Trajancypris sp. and Potamogpris smaragdina were found, indicating a freshwater to slightly oligohaline stagnant water body. The ostracod fauna of the NMO site, together with geochemical data, allow us to reconstruct a depositional environment of the margin at a shallow lake with brackish or saline springs nearby during the site's occupation by Middle Palaeolithic humans.
Additionally, Candona weltneri, Candona cf. meerfeldiana, C kingsleii, Cyclocypris laevis, C ophtalmica, Cyprideis sp., Fabaeformiscandona cf. fabaeformis, P. smaragdina, Pseudocandona depressa, Trajancypris sp, Zonocypris cf. costata and A. tepida could be recorded for the first time for the Pleistocene limnic strata of the Hula Basin. (C) 2014 Elsevier Ltd. All rights reserved.
The spring of Nadaouiyeh Ain Askar - Paleoecology of a Paleolithic oasis in arid central Syria
(2016)
The site Nadaouiyeh Aïn Askar, an ancient artesian spring near the village of El Kowm, Central Syria, is an example of long lasting human occupation in a desert environment throughout the Middle and Late Pleistocene. The excavations expose a succession of sedimentary units, containing an artifact assemblage assigned to the Acheulean techno-complex. Unit VI, attributed to the Marine Isotope Stage 13, is rich in ostracod valves and was chosen for the present environmental study. From these sediments Heterocypris salina, H. incongruens, Cyprideis torosa, Ilyocypris cf. bradyi, I. inermis, I. cf. gibba, Darwinula stevensoni, Plesiocypridopsis newtoni, Pseudocandona compressa, Candona cf. neglecta, Pseudocandona sp., Trajancypris sp., Physocypria sp. and Mixtacandona sp. are documented for the first time in the Middle Pleistocene of the arid environment of central Syria. Data from these microfossils as well as geochemical proxies implicate three phases, turning the wetland from a palustrine setting into a spring supplied pond with increasing salinity. The high mineralization of the spring waters enables a discussion about early hominin adaptability to brackish waters as drinking water resources, common within the steppe and desert environments along the “out-of-Africa”—corridor in the eastern Mediterranean.
Improved knowledge of retinoblastoma chemotherapy resistance is needed to raise treatment efficiency. The objective of this study was to test whether etoposide alters glucosyl-ceramide, ceramide, sphingosine, and sphingosine-1-phosphate (sphingosine-1-P) levels in parental retinoblastoma cells (WERI Rb1) or their etoposide-resistant subclones (WERI EtoR). WERI Rb1 and WERI EtoR were incubated with 400 ng/ml etoposide for 24 h. Levels of glucosyl-ceramides, ceramides, sphingosine, sphingosine-1-P were detected by Q-TOF mass spectrometry. Statistical analysis was done by ANOVA followed by Tukey post-hoc test (p < 0.05). The mRNA expression of sphingolipid pathways enzymes in WERI Rb1, WERI EtoR and four human retinoblastoma tissue samples was analyzed by quantitative real-time PCR. Pathways enzymes mRNA expression confirmed similarities of human sphingolipid metabolism in both cell lines and tissue samples, but different relative expression. Significant up-regulation of sphingosine was seen in both cell lines (p < 0.001). Only sphingosine-1-P up-regulation was significantly increased in WERI EtoR (p < 0.01), but not in WERI Rb1 (p > 0.2). Both cell lines upregulate pro-apoptotic sphingosine after etoposide incubation, but only WERI EtoR produces additional survival favorable sphingosine-1-P. These data may suggest a role of sphingosine-1-P in retinoblastoma chemotherapy resistance, although this seems not to be the only resistance mechanism.
There is an increasing interest in fusing data from heterogeneous sources. Combining data sources increases the utility of existing datasets, generating new information and creating services of higher quality. A central issue in working with heterogeneous sources is data migration: In order to share and process data in different engines, resource intensive and complex movements and transformations between computing engines, services, and stores are necessary.
Muses is a distributed, high-performance data migration engine that is able to interconnect distributed data stores by forwarding, transforming, repartitioning, or broadcasting data among distributed engines' instances in a resource-, cost-, and performance-adaptive manner. As such, it performs seamless information sharing across all participating resources in a standard, modular manner. We show an overall improvement of 30 % for pipelining jobs across multiple engines, even when we count the overhead of Muses in the execution time. This performance gain implies that Muses can be used to optimise large pipelines that leverage multiple engines.
Site-specific soil moisture and groundwater levels are key input parameters for ecological modeling. Obtaining such information in a comprehensive manner is difficult for large regions. We studied a floodplain region in the Federal State of Brandenburg, Germany, to examine the degree to which the average depth of groundwater tables can be derived from surface temperatures obtained by the ASTER radiospectrometer (spatial resolution of 90 m per pixel). A floristic ecological indicator representing the site-specific moisture level was applied to develop a proxy between the thermal satellite data and groundwater table depth. The use of spring scenes (late April to early May) from 2 years proved to be well suited for minimizing the effects of weather and land use. Vegetation surveys along transects that were 2 m wide across the pixel diagonals allowed for the calculation of average ecological moisture values of pixel-sites by applying Ellenberg-numbers. These values were used to calibrate the satellite data locally. There was a close relationship between surface temperature and the average ecological moisture value (R2 = 0.73). Average ecological moisture values were highly indicative of the average groundwater levels during a 7-year measurement series (R2 = 0.93). Satellite-supported thermal data from spring were suitable for estimating the average groundwater levels of low-lying grasslands on a larger scale. Ecological moisture values from the transect surveys effectively allowed the incorporation of relief heterogeneity within the thermal grid and the establishment of the correlation between thermal data and average groundwater table depth. Regression functions were used to produce a map of groundwater levels at the study site.
Water bodies are a highly abundant feature of Arctic permafrost ecosystems and strongly influence their hydrology, ecology and biogeochemical cycling. While very high resolution satellite images enable detailed mapping of these water bodies, the increasing availability and abundance of this imagery calls for fast, reliable and automatized monitoring. This technical work presents a largely automated and scalable workflow that removes image noise, detects water bodies, removes potential misclassifications from infrastructural features, derives lake shoreline geometries and retrieves their movement rate and direction on the basis of ortho-ready very high resolution satellite imagery from Arctic permafrost lowlands. We applied this workflow to typical Arctic lake areas on the Alaska North Slope and achieved a successful and fast detection of water bodies. We derived representative values for shoreline movement rates ranging from 0.40-0.56 m yr(-1) for lake sizes of 0.10 ha-23.04 ha. The approach also gives an insight into seasonal water level changes. Based on an extensive quantification of error sources, we discuss how the results of the automated workflow can be further enhanced by incorporating additional information on weather conditions and image metadata and by improving the input database. The workflow is suitable for the seasonal to annual monitoring of lake changes on a sub-meter scale in the study areas in northern Alaska and can readily be scaled for application across larger regions within certain accuracy limitations.