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  • 1
    Language: English
    In: Water resources research, 2015-04-26, Vol.51 (4), p.2760-2772
    Description: A new approach is developed to insert fiber optic cables vertically into the ground with direct push equipment. Groundwater temperatures may be measured along the cables with high spatial and temporal resolution using a Distributed Temperature Sensing system. The cables may be inserted up to depths of tens of meters in unconsolidated sedimentary aquifers. The main advantages of the method are that the cables are in direct contact with the aquifer material, the disturbance of the aquifer is minor, and no borehole is needed. This cost-effective approach may be applied to both passive and active heat tracer experiments. An active heat tracer experiment was conducted to estimate horizontal groundwater velocities in a managed aquifer recharge system in the Netherlands. Six fiber optic cables and a separate heating cable were inserted with a 1 m spacing at the surface. The heating cable was turned on for 4 days and temperatures were measured during both heating and cooling of the aquifer. Temperature measurements at the heating cable alone were used to estimate the magnitude of the groundwater velocity and the thermal conductivity of the solids. The direction of the velocity and heat capacity of the solids were estimated by including temperature measurements at the other fiber optic cables in the analysis. The latter analysis suffered from the fact that the cables were not inserted exactly vertical. The three-dimensional position of the fiber optic cables must be measured for future active heat tracer experiments.
    Subject(s): cone penetration test ; dts ; heat tracer test ; direct push equipment ; groundwater velocities
    ISSN: 0043-1397
    E-ISSN: 1944-7973
    Source: Alma/SFX Local Collection
    Source: EBSCOhost EJS
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  • 2
    Language: English
    In: Ground water, 2018-03-01, Vol.56 (2), p.288-299
    Description: An approach is presented to determine the seasonal variations in travel time in a bank filtration system using a passive heat tracer test. The temperature in the aquifer varies seasonally because of temperature variations of the infiltrating surface water and at the soil surface. Temperature was measured with distributed temperature sensing along fiber optic cables that were inserted vertically into the aquifer with direct push equipment. The approach was applied to a bank filtration system consisting of a sequence of alternating, elongated recharge basins and rows of recovery wells. A SEAWAT model was developed to simulate coupled flow and heat transport. The model of a two-dimensional vertical cross section is able to simulate the temperature of the water at the well and the measured vertical temperature profiles reasonably well. MODPATH was used to compute flowpaths and the travel time distribution. At the study site, temporal variation of the pumping discharge was the dominant factor influencing the travel time distribution. For an equivalent system with a constant pumping rate, variations in the travel time distribution are caused by variations in the temperature-dependent viscosity. As a result, travel times increase in the winter, when a larger fraction of the water travels through the warmer, lower part of the aquifer, and decrease in the summer, when the upper part of the aquifer is warmer.
    Subject(s): Models, Theoretical ; Soil ; Filtration ; Groundwater ; Water Wells ; Water Movements ; Tracers (Chemistry) ; Models ; Banks (Finance) ; Aquifers ; Index Medicus
    ISSN: 0017-467X
    E-ISSN: 1745-6584
    Source: Alma/SFX Local Collection
    Source: © ProQuest LLC All rights reserved〈img src="https://exlibris-pub.s3.amazonaws.com/PQ_Logo.jpg" style="vertical-align:middle;margin-left:7px"〉
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  • 3
    Language: English
    In: Science (American Association for the Advancement of Science), 2018-12-14, Vol.362 (6420), p.1297-1301
    Description: East Africa has provided the earliest known evidence for Oldowan stone artifacts and hominin-induced stone tool cutmarks dated to ~2.6 million years (Ma) ago. The ~1.8-million-year-old stone artifacts from Ain Hanech (Algeria) were considered to represent the oldest archaeological materials in North Africa. Here we report older stone artifacts and cutmarked bones excavated from two nearby deposits at Ain Boucherit estimated to ~1.9 Ma ago, and the older to ~2.4 Ma ago. Hence, the Ain Boucherit evidence shows that ancestral hominins inhabited the Mediterranean fringe in northern Africa much earlier than previously thought. The evidence strongly argues for early dispersal of stone tool manufacture and use from East Africa or a possible multiple-origin scenario of stone technology in both East and North Africa.
    Subject(s): Bones ; Natural history ; Index Medicus ; Humanities and Social Sciences ; Archaeology and Prehistory
    ISSN: 0036-8075
    ISSN: 0883-6353
    E-ISSN: 1095-9203
    E-ISSN: 1520-6548
    Source: Single Journals
    Source: Academic Search Ultimate
    Source: Alma/SFX Local Collection
    Source: EBSCOhost EJS
    Source: © ProQuest LLC All rights reserved〈img src="https://exlibris-pub.s3.amazonaws.com/PQ_Logo.jpg" style="vertical-align:middle;margin-left:7px"〉
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  • 4
    Language: English
    In: Water resources research, 2019, Vol.55 (1), p.811-826
    Description: An approach is presented to determine groundwater flow in unconsolidated aquifers with a heat pulse response test using a heating cable and a fiber-optic cable. The cables are installed together using direct push so that the cables are in direct contact with the aquifer. The temperature response is measured for multiple days along the fiber-optic cable with Distributed Temperature Sensing (DTS). The new approach fits a two-dimensional analytical solution to the temperature measurements, so that the specific discharge can be estimated without knowledge of the position of the fiber-optic cable relative to the heating cable. Two case studies are presented. The first case study is at a managed aquifer recharge system where fiber-optic cables are inserted 15 m deep at various locations to test the fitting procedure. Similar and relatively large specific discharges are found at the different locations with little vertical variation (0.4–0.6 m/day). The second case study is at a polder, where the water level is maintained 2 m below the surrounding lakes, resulting in significant groundwater flow. The heating and fiber-optic cables are inserted to a depth of 45 m. The specific discharge varies 0.07–0.1 m/day and is significantly larger in a thin layer at 30-m depth. It is shown with numerical experiments that the estimated specific discharge is smoother than in reality due to vertical conduction, but the peak specific discharge is estimated correctly for layers thicker than ∼1.5 m.
    ISSN: 0043-1397
    E-ISSN: 1944-7973
    Source: Alma/SFX Local Collection
    Source: EBSCOhost EJS
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  • 5
    Language: English
    In: Palaeobiodiversity and palaeoenvironments, 2020-06, Vol.100 (2), p.321-349
    ISSN: 1867-1594
    E-ISSN: 1867-1608
    Source: Alma/SFX Local Collection
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  • 6
    Language: English
    In: Quaternary research, 2017-11, Vol.88 (3), p.537-550
    Description: The skull of the extinct rhinoceros Stephanorhinus kirchbergensis (Jäger, 1839) was discovered in the Chondon River valley (Arctic Yakutia, Russia) during the summer of 2014. This is the first find of Stephanorhinus above the Arctic Circle, expanding significantly the known geographic range of the genus. 14C dating and geologic evidence indicate that the skull dates to between 48,000 and 70,000 yr, corresponding to Marine Oxygen Isotope Stage 4/3. It is thus among the latest records of this species. To explore the evolutionary and natural history of this relatively unknown animal, we performed morphological, dietary, and genetic analyses. Phylogenetic inference based on a complete mitochondrial genome sequence confirms the systematic placement of Stephanorhinus as most closely related to the extinct woolly rhinoceros, Coelodonta. Food remains in the fossas of the cheek teeth, identified as Larix, Vaccinium, Betula sp., Aulacomnium, and dicotyledonous herbs and grasses, suggest a mixed feeder’s diet. Microwear analysis suggests that, during the last months of its life, this individual fed predominantly on leaves and twigs. The habitat of Stephanorhinus comprised grassland and open woodland that were characterized by moist and cold climate conditions, similar to those in the region today.
    Subject(s): Ethnography ; Grasslands ; Teeth ; Soil sciences ; Science ; River networks ; Ecology ; Sediments ; Nutrition research ; Archaeology ; Precipitation ; Diet ; Winter ; Polar environments ; Vegetation ; Stratigraphy
    ISSN: 0033-5894
    E-ISSN: 1096-0287
    Source: Cambridge Journals
    Source: Alma/SFX Local Collection
    Source: ProQuest Central
    Source: © ProQuest LLC All rights reserved〈img src="https://exlibris-pub.s3.amazonaws.com/PQ_Logo.jpg" style="vertical-align:middle;margin-left:7px"〉
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  • 7
    Language: English
    In: Public administration (London), 2007-12, Vol.85 (4), p.1077-1095
    Description: By focusing on institutions (rules for action) and routines (patterned behaviour) our intention is to contribute to the understanding of government policy and its outcomes in health and social care. We analysed data to show how the relationship between a new idea for a routine and new rules from the government on the one hand, and existing rules and routines in society on the other, as well as the interaction between rule makers and rule takers (i.e. those who are governed by those rules), have an impact on the change or maintenance of routines. The data concern the case of government policy for need assessment (that is, assessment of needs) in The Netherlands. As our discussion will show, even a national government, however, is not able to completely impose its will on other agents in order to change existing routines. The concept of ‘negotiated order’ helps us to understand why. In the case reported here, the Dutch government and the home care agencies had to exercise give and take, the outcome being a suboptimal result for both.
    Subject(s): Exercise
    ISSN: 0033-3298
    E-ISSN: 1467-9299
    Source: Business Source Ultimate
    Source: Alma/SFX Local Collection
    Source: © ProQuest LLC All rights reserved〈img src="https://exlibris-pub.s3.amazonaws.com/PQ_Logo.jpg" style="vertical-align:middle;margin-left:7px"〉
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  • 8
    Language: English
    In: Quaternary research, 2017-11, Vol.88 (3), p.570-570
    Subject(s): Polar environments
    ISSN: 0033-5894
    E-ISSN: 1096-0287
    Source: Cambridge Journals
    Source: Alma/SFX Local Collection
    Source: ProQuest Central
    Source: © ProQuest LLC All rights reserved〈img src="https://exlibris-pub.s3.amazonaws.com/PQ_Logo.jpg" style="vertical-align:middle;margin-left:7px"〉
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  • 9
    Language: English
    In: Journal of quaternary science, 2020-05, Vol.35 (4), p.539-558
    Description: ABSTRACT The sedimentary succession exposed in the Gorzów Wielkopolski area includes Eemian Interglacial (MIS 5e) or Early Weichselian (MIS 5d–e) deposits. The sedimentary sequence has been the object of intense interdisciplinary study, which has resulted in the identification of at least two palaeolake horizons. Both yielded fossil remains of large mammals, alongside pollen and plant macrofossils. All these proxies have been used to reconstruct the environmental conditions prevailing at the time of deposition, as well as to define the geological context and the biochronological position of the fauna. Optically stimulated luminescence dating of the glaciofluvial layers of the GS3 succession to 123.6 ± 10.1 (below the lower palaeolake) and 72.0 ± 5.2 ka (above the upper palaeolake) indicate that the site formed during the Middle–Late Pleistocene (MIS 6 – MIS 5). Radiocarbon‐dating of the lacustrine organic matter revealed a tight cluster of Middle Pleniglacial Period (MIS 3) ages in the range of ~41–32 ka cal bp (Hengelo – Denekamp Interstadials). Holocene organic layers have also been found, with 14C ages within a range of 4330–4280 cal bp (Neolithic). Pollen and plant macrofossil records, together with sedimentological and geochemical data, confirm the dating to the Eemian Interglacial.
    Subject(s): palynology and macrofossil analysis ; radiocarbon dating ; Quaternary stratigraphy ; Eemian Interglacial ; OSL dating
    ISSN: 0267-8179
    E-ISSN: 1099-1417
    Source: Alma/SFX Local Collection
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  • 10
    Language: English
    In: Scientific reports, 2017-03-02, Vol.7 (1), p.43460-43460
    Description: Kaldar Cave is a key archaeological site that provides evidence of the Middle to Upper Palaeolithic transition in Iran. Excavations at the site in 2014-2015 led to the discovery of cultural remains generally associated with anatomically modern humans (AMHs) and evidence of a probable Neanderthal-made industry in the basal layers. Attempts have been made to establish a chronology for the site. These include four thermoluminescence (TL) dates for Layer 4, ranging from 23,100 ± 3300 to 29,400 ± 2300 BP, and three AMS radiocarbon dates from charcoal samples belonging to the lower part of the same layer, yielding ages of 38,650-36,750 cal BP, 44,200-42,350 cal BP, and 54,400-46,050 cal BP (all at the 95.4% confidence level). Kaldar Cave is the first well-stratified Late Palaeolithic locality to be excavated in the Zagros which is one of the earliest sites with cultural materials attributed to early AMHs in western Asia. It also offers an opportunity to study the technological differences between the Mousterian and the first Upper Palaeolithic lithic technologies as well as the human behaviour in the region. In this study, we present a detailed description of the newly excavated stratigraphy, quantified results from the lithic assemblages, preliminary faunal remains analyses, geochronologic data, taphonomic aspects, and an interpretation of the regional paleoenvironment.
    Subject(s): Neanderthals - physiology ; Radiometric Dating - methods ; Neanderthals - psychology ; Reptiles - physiology ; Humans ; Neanderthals - anatomy & histology ; Birds - physiology ; Carnivory - physiology ; Artiodactyla - physiology ; Fossils ; Perissodactyla - physiology ; Animals ; Iran ; Geologic Sediments - analysis ; Archaeology - methods ; Amphibians - physiology ; Caves ; Carbon Radioisotopes ; Rodentia - physiology ; Data processing ; Stratigraphy ; Lithic ; Hominids ; Charcoal ; Taphonomy ; Index Medicus
    ISSN: 2045-2322
    E-ISSN: 2045-2322
    Source: Nature Open Access
    Source: Academic Search Ultimate
    Source: PubMed Central
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