17 research outputs found

    Geoelectrical Possibilities of Detecting Stream Channels in Carbonate Rocks

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    Several geoelectrical resistivity methods that may be used to determine the position and flow characteristics of underground water associated with carbonate bedrock and karst development are considered. The most promising method studied employs depth soundings patterned after Schlumberger. The plotting of half electrode separation against apparent resistivity yields a curve which may be used to discriminate between lateral and vertical inhomogeneities in bedrock. A network of depth soundings of this type ultimately may lead to a map that will show geoelectrical anisotropies that may be used to analyze subsurface water courses in carbonate rock

    Methods of determining aquifer storage capacity and fresh-saline water interfaces by geoelectrical investigations

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    Students supported: One graduate student supportedGeoelectrical investigations in Grundy County of northwestern Missouri where the groundwater resources of the glacial deposits have already been examined through an extensive drilling program by the Missouri Geological Survey and Water Resources, indicate that water-bearing gravel deposits can be distinguished from glacial deposits containing appreciable amounts of clay and limited, amounts of water. The Schlumberger method used for the geoelectric depth soundings in the vicinity of the Survey's drillholes demonstrates the exploratory usefulness of the method in that it can partly replace the more expensive procedure of drilling. The method also provides improved interpretation between drillholes. Results of the investigation show that, in the area, clay has a resistivity below 20(omega)m, that the fresh water-bearing gravel at the bottom of the buried glacial stream channels has a resisitivity of 40 to 50 (omega)m, and that the near surface glacial gravel deposits have a resistivity above 100 (omega)m. Interpretation of the depth soundings and the conductivity of water obtained from a local well implies that its water is drawn from the saline water of the bedrock. A recommendation is made for the quality improvement of this particular well.Project # A-046-MO Agreement # 14-31-0001-352

    The detection of subsurface stream channels in carbonate rocks by geoelectrical methods

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    Student supported: 1 Student AssistantThe distinction of partially dissolved from compact carbonate rocks and from the alluvial overburden is a major problem in geological engineering and water resources. Geoelectrical depth soundings after Schlumberger were applied over karst terraines in three locations of the Ozarks in Missouri. The zone of dissolved carbonate rock shows intermediate resistivities between low values for the overburden and extremely high values for the compact rock. The main part of the investigation was directed towards solving the underground flow and disappearance of Logan Creek near Ellington, Missouri. Combined geoelectrical and gravity surveys under consideration of some near surface seismic refractions indicate zones of increased depth and degree of dissolution at the Ellington Fault. A detailed gravity profile across the fault shows a negative anomaly with a minimum of -2.0 mgal, which extends over approximately 3 miles with large lateral gradients. A theoretical model can explain the anomaly if the depth of the cavernous limestone has a maximum of 350 feet and if the bulk volume of fissures and stream channels amounts to 15 percent. The coincidence between the fault and the negative anomaly suggests that ruptures along fault planes weakened the rock so that chemical dissolution from surface waters had a greater penetration.Project # A-065-MO Agreement # 14-31-0001-382

    Justice from an interdisciplinary perspective: the impact of the revolution in Human Sciences on Peace Research and International Relations

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    Peace and justice have been a preferred couple in theoretical writings - but what do we know about their empirical relationship? Insights from other disciplines suggest that humans are highly sensitive to violations of justice and that justice concerns permeate social relations. Neuroscientists have located the parts of the brain responsible for negative reactions to violation of claims for justice. Evolutionary biologists have identified rules of distribution and retribution not only in early human societies but among other socially living species as well. Psychologists have observed the emergence of a sense of justice in very early childhood, while behavioral economists have identified behavior of average persons in experiments that deviated significantly from the model of the "economic man" and could only be explained by a sense of justice. The chapter summarizes these findings and outlines their implications for peace research. It highlights the ambivalent nature of justice for social relations. Justice concerns can exacerbate conflicts between individuals and groups but justice can also provide standards for arriving at durable peaceful solutions to conflicts. Understanding these ambivalences and their repercussions for international and intrastate relations provides a promising path towards understanding conflict dynamics

    Monitoring integrity and localization of modified single-stranded RNA oligonucleotides using ultrasensitive fluorescence methods

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    Short single-stranded oligonucleotides represent a class of promising therapeutics with diverse application areas. Antisense oligonucleotides, for example, can interfere with various processes involved in mRNA processing through complementary base pairing. Also RNA interference can be regulated by antagomirs, single-stranded siRNA and single-stranded microRNA mimics. The increased susceptibility to nucleolytic degradation of unpaired RNAs can be counteracted by chemical modification of the sugar phosphate backbone. In order to understand the dynamics of such single-stranded RNAs, we investigated their fate after exposure to cellular environment by several fluorescence spectroscopy techniques. First, we elucidated the degradation of four differently modified, dual-dye labeled short RNA oligonucleotides in HeLa cell extracts by fluorescence correlation spectroscopy, fluorescence cross-correlation spectroscopy and Forster resonance energy transfer. We observed that the integrity of the oligonucleotide sequence correlates with the extent of chemical modifications. Furthermore, the data showed that nucleolytic degradation can only be distinguished from unspecific effects like aggregation, association with cellular proteins, or intramolecular dynamics when considering multiple measurement and analysis approaches. We also investigated the localization and integrity of the four modified oligonucleotides in cultured HeLa cells using fluorescence lifetime imaging microscopy. No intracellular accumulation could be observed for unmodified oligonucleotides, while completely stabilized oligonucleotides showed strong accumulation within HeLa cells with no changes in fluorescence lifetime over 24 h. The integrity and accumulation of partly modified oligonucleotides was in accordance with their extent of modification. In highly fluorescent cells, the oligonucleotides were transported to the nucleus. The lifetime of the RNA in the cells could be explained by a balance between release of the oligonucleotides from endosomes, degradation by RNases and subsequent depletion from the cells

    Dictator Games: A Meta Study

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    Gravity Investigations over a Salt Structure near Lübbecke, Northern Germany

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    A detailed gravity survey was conducted parallel to the “Wiehengebirge” northwest of Minden in Northern Germany. The survey localized between Liibbecke and Levern a salt deposit, which is known as “Münder Mergel” salt of the Upper Jurassic. The salt deposit forms a cylindrical structure with an axis striking NWW. With a deep drill hole detailed interpretation was possible using the polygon method of TALWANI, WORZEL and LANDISMAN [1959], The section shapes of salt bodies under eight profiles show asymmetrical figures of two salt units. Both increase in thickness strongly to the northeast, where the salt is interrupted by a fault zone. Here the strong gradient of the residual anomaly can only be explained by an increase of thickness and rise of the upper salt unit to about 50 m below the surface. This accounts for a number of sulfur and salt wells along the strike direction of the fault zone

    Hydrogeological characterization of a karst aquifer with geoelectrical depth soundings

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    The use of geoelectrics and test wells for the assessment of groundwater quality of a coastal industrial site

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    Using geoelectrical depth soundings, potential groundwater pollution was assessed on a former shipyard of the Newport Naval Base, Rhode Island, USA. Besides an increase of the total dissolved solids (TDS), toxic organic compounds and metals were expected in the saturated zone. Two nested test wells were used to support the geoelectrical interpretation and a third one was located in a poorly accessible place. Non-invasive and cost-effective geoelectrics is representative for a sizeable volume, but the field data are non-unique with respect to the interpretation. Test wells, on the other hand, provide precise data, but they are laterally confined, so that a combination of both methods optimizes the results. This survey concentrates on the freshwater-saturated zone of glacial sediments that range in thickness between 1 and 15 m. The sediment is a poorly sorted till that is described as silty, gravelly sand with a low hydraulic conductivity of considerable heterogeneity. The major effort concentrated on a 12-m wide strip located between a sheet pile bulkhead along the shore and a building in which chemicals were stored and handled. This strip was the only place where depth soundings with a depth penetration extending below the freshwater-saturated zone were logistically possible. Other places were unsuitable because of conductive constructions at the surface, concrete pavements, and adjacent buildings. In spite of poor data quality, four of the five geoelectrical depth soundings were identified to be of QH-type (ρ1 \u3eρ2 \u3eρ3 \u3cρ4), with the following hydrogeological correspondence: unsaturated-, freshwater-saturated, seawater-saturated zone, and non-conductive tight glacial till and shale bedrock. The target of this investigation is the freshwater-saturated zone, which is qualitatively recognized on four of the five sounding curves. To avoid an underestimation of the interpreted layer resistivities, the lateral effect from the seawater and iron sheet pile bulkhead was corrected. It was approximated with a semi-infinite vertical boundary between the aquifer and a conducting medium using the image method. Low aquifer resistivities are usually associated with potential pollution in terms of high concentrations of TDS. A semi-quantitative attempt is described to correlate bulk layer with pore water resistivity and finally with equivalent TDS. Because of the presence of clay-sized particles in the sediment, the bulk electrical conductivity is caused by water conduction through the pore channels and the surface conductivity of the particles. Lab sample measurements of resistivity on samples recovered from the test wells provided a calibration curve for the bulk conductivity-water conductivity relationship. In spite of complications due to surface constructions and the heterogeneity of the freshwater-saturated till, it was possible to identify high conductivity groundwater with a conductivity on the order of 3000 μS/cm that is equivalent to approximately 1950 ppm TDS. It is not possible to determine whether or how much of the TDS originates from seawater overwash and how much is attributable to shipyard activities. Test wells, however, showed objectionable amounts of dissolved metals and adsorbed toxic organic compounds. © 2002 Elsevier Science B.V. All rights reserved
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