Dynamic interpretation of slug tests in highly permeable aquifers

This is the published version. Copyright American Geophysical Union[1] Considerable progress has been made in developing a theoretical framework for modeling slug test responses in formations with high hydraulic conductivity K. However, several questions of practical significance remain unresolved. Given the rapid and often oscillatory nature of test responses, the traditional hydrostatic relationship between the water level and the transducer-measured head in the water column may not be appropriate. A general dynamic interpretation is proposed that describes the relationship between water level response and transducer-measured head. This theory is utilized to develop a procedure for transforming model-generated water level responses to transducer readings. The magnitude of the difference between the actual water level position and the apparent position based on the transducer measurement is a function of the acceleration and velocity of the water column, test geometry, and depth of the transducer. The dynamic approach explains the entire slug test response, including the often-noted discrepancy between the actual initial water level displacement and that measured by a transducer in the water column. Failure to use this approach can lead to a significant underestimation of K when the transducer is a considerable distance below the static water level. Previous investigators have noted a dependence of test responses on the magnitude of the initial water level displacement and have developed various approximate methods for analyzing such data. These methods are re-examined and their limitations clarified. Practical field guidelines are proposed on the basis of findings of this work. The soundness of the dynamic approach is demonstrated through a comparison of K profiles from a series of multilevel slug tests with those from dipole-flow tests performed in the same wells

SMART Cables for Observing the Global Ocean: Science and Implementation

The ocean is key to understanding societal threats including climate change, sea level rise, ocean warming, tsunamis, and earthquakes. Because the ocean is difficult and costly to monitor, we lack fundamental data needed to adequately model, understand, and address these threats. One solution is to integrate sensors into future undersea telecommunications cables. This is the mission of the SMART subsea cables initiative (Science Monitoring And Reliable Telecommunications). SMART sensors would “piggyback” on the power and communications infrastructure of a million kilometers of undersea fiber optic cable and thousands of repeaters, creating the potential for seafloor-based global ocean observing at a modest incremental cost. Initial sensors would measure temperature, pressure, and seismic acceleration. The resulting data would address two critical scientific and societal issues: the long-term need for sustained climate-quality data from the under-sampled ocean (e.g., deep ocean temperature, sea level, and circulation), and the near-term need for improvements to global tsunami warning networks. A Joint Task Force (JTF) led by three UN agencies (ITU/WMO/UNESCO-IOC) is working to bring this initiative to fruition. This paper explores the ocean science and early warning improvements available from SMART cable data, and the societal, technological, and financial elements of realizing such a global network. Simulations show that deep ocean temperature and pressure measurements can improve estimates of ocean circulation and heat content, and cable-based pressure and seismic-acceleration sensors can improve tsunami warning times and earthquake parameters. The technology of integrating these sensors into fiber optic cables is discussed, addressing sea and land-based elements plus delivery of real-time open data products to end users. The science and business case for SMART cables is evaluated. SMART cables have been endorsed by major ocean science organizations, and JTF is working with cable suppliers and sponsors, multilateral development banks and end users to incorporate SMART capabilities into future cable projects. By investing now, we can build up a global ocean network of long-lived SMART cable sensors, creating a transformative addition to the Global Ocean Observing System

Combined analysis of 08/09 and 2010 experiments

At a meeting held in Canberra in July 2010, it was agreed to undertake a study to investigate whether a combined analysis of the 08/09 series of LMA experiments and the single 2010 experiment was feasible. The current protocol for classification of lines relies on obtaining information from two valid LMA screening experiments. The analysis of the 08/09 series of experiments represented the first attempt to undertake a combined analysis of LMA screening experiments. It is well known (see for example, Mrode [1995]) that the optimum methodology to evaluate genetic material for eventual selection is to use a multivariate or multi-trait analysis. This multi-trait analysis takes account of the relationships which exist between the different traits. In our example, each experiment is considered as a trait and so for these data we have three traits, one for each experiment

The Dillow’s Ridge Site and the Production of Mill Creek Chert Tools

The Dillow\u27s Ridge site (11 U635) is a small Mississippian village situated on an unplowed hilltop near the largest known Mill Creek chert quarry in Union County, Illinois. The site was both a permanent residential settlement and a major workshop where Mill Creek chert tools were produced for nonlocal use. Radiocarbon dates document the occupation from the late 1200s A.D. to A.D. 1450 or 1500. The production debris and rejects indicate that the major “export products were hoes and Ramey knives. Although the quantity of lithic debris on the site is very impressive, estimates of annual production of large biface implements are in the hundreds per year and not thousands. This level of production was easily attained by part-time specialists within a small community without major distortion of normal domestic and food-getting activities. Production and trade of these implements was also not a source of significant prestige or wealth for the producers

Electronic Pedagogy and Future University Business Models

Based on the International Conference on Information Systems’ (ICIS) 2014 senior scholars’ forum, we share insights on the relationship between evolving university business models and the adoption of electronic pedagogy. In recent years, particularly with the initiation of MOOCs, the potential for delivering high-quality and widely distributed coursework has expanded. However, particular instances of MOOCs and other electronic pedagogies do not guarantee equally high-quality educational outcomes for all participants. For example, some studies have suggested that most individuals completing MOOC coursework already have baccalaureate degrees, which contrasts with the idea that individuals undertake such coursework as a substitute for traditional degree programs. With this paper, we present varied experiences and views on using electronic pedagogy and report on both the conclusions and new questions raised about adopting these technologies for universities

Large-area submillimeter resolution CdZnTe strip detector for astronomy

We report the first performance measurements of a sub-millimeter CdZnTe strip detector developed as a prototype for space-borne astronomical instruments. Strip detector arrays can be used to provide two-dimensional position resolution with fewer electronic channels than pixellated arrays. Arrays of this type and other candidate technologies are under investigation for the position-sensitive backplane detector for a coded-aperture telescope operating in the range of 30 - 300 keV. The prototype is a 1.4 mm thick, 64 multiplied by 64 stripe CdZnTe array of 0.375 mm pitch in both dimensions, approximately one square inch of sensitive area. Pulse height spectra in both single and orthogonal stripe coincidence mode were recorded at several energies. The results are compared to slab- and pixel-geometry detector spectra. The room-temperature energy resolution is less than 10 keV (FWHM) for 122 keV photons with a peak-to-valley ratio greater than 5:1. The response to photons with energies up to 662 keV appears to be considerably improved relative to that of previously reported slab and pixel detectors. We also show that strip detectors can yield spatial and energy resolutions similar to those of pixellated arrays with the same dimensions. Electrostatic effects on the pulse heights, read-out circuit complexity, and issues related to design of space borne instruments are also discussed

Development of an orthogonal-stripe CdZnTe gamma radiation imaging spectrometer

We report performance measurements of a sub-millimeter resolution CdZnTe strip detector developed as a prototype for astronomical instruments operating with good efficiency in the 30-300 keV photon energy range. The prototype is a 1.4 mm thick, 64×64 contact stripe CdZnTe array of 0.375 mm pitch in both dimensions. Pulse height spectra were recorded in orthogonal-stripe coincidence mode which demonstrate room-temperature energy resolution \u3c10 keV (FWHM) for 122 keV photons with a peak-to-valley ratio \u3e5:1. Good response is also demonstrated at higher energies using a coplanar grid readout configuration. Spatial resolution capabilities finer than the stripe pitch are demonstrated. We present the image of a 133Ba source viewed through a collimator slit produced by a 4×4 stripe detector segment. Charge signals from electron and hole collecting contacts are also discussed

Gut inflammation provides a respiratory electron acceptor for Salmonella.

Salmonella enterica serotype Typhimurium (S. Typhimurium) causes acute gut inflammation by using its virulence factors to invade the intestinal epithelium and survive in mucosal macrophages. The inflammatory response enhances the transmission success of S. Typhimurium by promoting its outgrowth in the gut lumen through unknown mechanisms. Here we show that reactive oxygen species generated during inflammation react with endogenous, luminal sulphur compounds (thiosulphate) to form a new respiratory electron acceptor, tetrathionate. The genes conferring the ability to use tetrathionate as an electron acceptor produce a growth advantage for S. Typhimurium over the competing microbiota in the lumen of the inflamed gut. We conclude that S. Typhimurium virulence factors induce host-driven production of a new electron acceptor that allows the pathogen to use respiration to compete with fermenting gut microbes. Thus the ability to trigger intestinal inflammation is crucial for the biology of this diarrhoeal pathogen

CLINICAL AND BIOMECHANICAL COMPARISONS BETWEEN YOUTH PITCHERS WITH AND WITHOUT A HISTORY OF THROWING ARM PAIN OR INJUR

This study aimed to determine if there are clinical and kinematic differences in youth pitchers with a self-reported history of throwing arm pain or injury (PI) to those without (NPI). Forty male baseball pitchers ages 9 to 14 years old were divided into a PI group (n=20) and a NPI group (n=20). Injury history, pitching exposure, subject demographics, range of motion, and strength measurements were collected, along with throwing arm kinematics via a motion capture system. When comparing PI and NPI, significant physical differences were observed, with a greater presence of axillary hair, increased forearm length and decreased shoulder internal rotation strength in PI. No significant differences of upper limb motion during pitching were reported. When considering youth pitchers, evidence of physical maturity, arm length, and strength could be important factors in developing pain or injury