Search results for "Stage"
showing 10 items of 1393 documents
Luminescence dating of loess deposits from the Remagen-Schwalbenberg site, Western Germany
2015
Geochronometria 42(1), 67-77 (2015). doi:10.1515/geochr-2015-0008
Variability in the vertical structure of the water column and paleoproductivity reconstruction in the central-western Mediterranean during the Late P…
2008
Abstract A sedimentary sequence spanning Marine Isotope Stage (MIS) 6 to MIS 2 in core LC07, recovered in the central Mediterranean, has been investigated in order to produce a high-resolution paleoceanographic reconstruction. The changes in productivity deduced from calcareous plankton relative abundances and independently confirmed by the Ba XS fluctuations are linked to the stability of the water column which is mainly controlled by the water mass temperature. During glacial intervals, productivity was generally enhanced. Oligotrophic and warmer water masses with a deepened seasonal thermocline can be inferred for most of MIS5. The magnetic properties of the sediment show increased occur…
Upper pleistocene interstratal piping-cave speleogenesis: The seso cave system (central pyrenees, northern spain)
2015
The Seso Cave System (SCS, South Central Pyrenees, Northeastern Spain) develops in poorly soluble marly interstratum between limestone beds of Eocene age. We propose an innovative and singular pseudokarstic speleogenetic model under vadose conditions based on cave morphological evidence, physicochemical and mineralogical characteristics of the Eocene marly host rock, U-Th dating of cave deposits, and local geological and geomorphological information. Eocene marls are shown to be sensitive to dispersion processes supported by their high clay content and the high concentration of sodium and low electrical conductivity in the seepage water. Runoff inside the cave results from water that infilt…
21. Abrupt change of El Niño activity off Peru during stage MIS 5e-d
2007
Abstract High-resolution proxy data for El Nino variability during the last glacial cycle were derived from a laminated marine sediment core from a region whose climatology and oceanography is strongly affected by ENSO variability. The proxies used are the seasurface temperature and the lithic flux from the continent onto the continental shelf that is largely controlled by the river flood discharge after strong El Nino rainfall in northern and northern central Peru. The focus of this paper is on an abrupt, possibly orbitally driven change of El Nino activity within marine isotope stage 5e. A similar sharp decline of El Nino activity is also observed during the middle of the Holocene intergl…
Eolian and fluvial sedimentation in the southwestern Sinai Mountains, Egypt: a record of flash floods during the late Pleistocene
2012
Wadis emerging from the southwestern Sinai Mountains (Egypt) westwards to the Gulf of Suez are filled by >40 m thick late Pleistocene sediments, which have been subsequently incised to bedrock after the Last Glacial Maximum (LGM). Sedimentation and erosion resulted from changes in the basin's hydrological conditions caused by climate variations. Sediment characteristics indicate distinct processes ranging from high to low energy flow regimes. Airborne material is important as a sediment source. The fills are associated with alluvial fans at wadi mouths at the mountain fronts. Each alluvial fan is associated and physically correlated with the respective sediment fill in its contributi…
Evolucion paleoambiental desde el Holoceno temprano hasta la actualidad del marjal de Almenara (Mediterráneo occidental)
2018
The main aim of this study is to characterize the different stages in the palaeoenvironmental evolution of the Almenara marsh, Spain, from the early Holocene to the present day. This marsh is one of the most important in Castellón province. Five cores extracted from the marsh underwent sedimentological analysis, micropalaeontological study (foraminifera, ostracods and gastropods) and 14C dating. The results show that before the maximum transgression of the Mediterranean during the Marine Isotope Stage 1 (5500 cal yr. BP dating in the Almenara marsh), the area was occupied by a brackish marsh (prior to the 8.2 ka event). During the middle Holocene, the regional sea level rise and later stabi…
Why do people avoid and postpone the use of voice assistants for transactional purposes? A perspective from decision avoidance theory
2022
Consumers increasingly adopt artificial intelligence (AI) enabled voice assistants (VAs) for transactional and non-transactional uses due to these devices’ inherent affordances, such as their ease of use and convenience. Despite the widespread adoption of VAs in recent times, consumers continue to avoid using VAs for transactional purposes. Currently, we have a limited understanding of the various antecedents and consequences of consumer decision avoidance in the context of VAs. This study aims to bridge this gap by adopting the decision avoidance theory as a theoretical lens and a convergent mixed-methods approach to identify the antecedents (i.e. cognitive biases and nudging) and conseque…
Irreversible Multilayer Adsorption
1993
Random sequential adsorption (RSA) models have been studied due to their relevance to deposition processes on surfaces. The depositing particles are represented by hard-core extended objects; they are not allowed to overlap. Numerical Monte Carlo studies and analytical considerations are reported for 1D and 2D models of multilayer adsorption processes. Deposition without screening is investigated, in certain models the density may actually increase away from the substrate. Analytical studies of the late stage coverage behavior show the crossover from exponential time dependence for the lattice case to the power law behavior in the continuum deposition. 2D lattice and continuum simulations r…
Analysis of the packing stage in injection molding of thermoplastic polymers
1988
Injection molding tests were performed on a Ny 66 resin. Data are presented on the mass entering the mold during the packing-holding stage as a function of filling flow rate and holding time. The experimental results are discussed on the basis of a simple model of the packing-holding stage. Only a small part of the density increase due to crystallization seems to be compensated by extra flow during the packing-holding stage.
Demonstration of remote optical measurement configuration that correlates to glucose concentration in blood
2010
An optical approach allowing the extraction and the separation of remote vibration sources has recently been proposed. The approach has also been applied for medical related applications as blood pressure and heart beats monitoring. In this paper we demonstrate its capability to monitor glucose concentration in blood stream. The technique is based on the tracking of temporal changes of reflected secondary speckle produced in human skin (wrist) when being illuminated by a laser beam. A temporal change in skin’s vibration profile generated due to blood pulsation is analyzed for estimating the glucose concentration. Experimental tests that were carried out in order to verify the proposed appro…