Characterizing near-surface erosion variability in claypan soils

Master of ScienceDepartment of Civil EngineeringStacey E. KuleszaGretchen F. SassenrathSoil erosion due to an underlying claypan layer ultimately impairs water resources and limits crop yield in agricultural fields. Claypan soils cover approximately 40,469 square kilometers in the United States and are characterized by a highly impermeable layer underlying surficial soil. The objective of this research was to delineate the variability of soil properties, including soil erodibility, in claypan soils. Understanding how soil properties change in the subsurface is critical to understanding the processes exacerbating soil loss in claypan regions. Geophysical methods were used to determine the spatial variability of surface soil (apparent electrical conductivity) and the soil stratigraphy between a high and low apparent electrical conductivity areas (electrical resistivity tomography). Laboratory (erosion function apparatus) and in-situ (“mini” jet erosion test), erosion methods were used to identify the variability in soil erosion with depth in claypan soils. Laboratory test were used to classify and determine the strength and permeability of claypan soils. The results of this study indicate the surficial soil has a higher hydraulic conductivity and is more erodible than the underling claypan layer, which has a lower hydraulic conductivity and is resistant to erosion. As a result, surficial soil is being eroded by the process of undermining due to an underlying impermeable claypan layer. This research is significant because there is limited knowledge of erosion on claypan soils. The knowledge gained from this study will aid in the quantification of erosion on claypan soils in existing erosion models at field and watershed scales

The NO upsilon A Far Detector Data Acquisition System

The NOvA experiment is a long-baseline neutrino experiment designed to make measurements to determine the neutrino mass hierarchy, neutrino mixing parameters and CP violation in the neutrino sector. In order to make these measurements the NOvA collaboration has designed a highly distributed, synchronized, continuous digitization and readout system that is able to acquire and correlate data from the Fermi lab accelerator complex (NuMI), the NOvA near detector at the Fermi lab site and the NOvA far detector which is located 810 km away at Ash River, MN. This system has unique properties that let it fully exploit the physics capabilities of the NOvA detector. The design of the NOvA DAQ system and its capabilities are discussed in this paper

Augmenting TV Viewing using Acoustically Transparent Auditory Headsets

This paper explores how acoustically transparent auditory headsets can improve TV viewing by intermixing headset and TV audio, facilitating personal, private auditory enhancements and augmentations of TV content whilst minimizing occlusion of the sounds of reality. We evaluate the impact of synchronously mirroring select audio channels from the 5.1 mix (dialogue, environmental sounds, and the full mix), and selectively augmenting TV viewing with additional speech (e.g. Audio Description, Directors Commentary, and Alternate Language). For TV content, auditory headsets enable better spatialization and more immersive, enjoyable viewing; the intermixing of TV and headset audio creates unique listening experiences; and private augmentations offer new ways to (re)watch content with others. Finally, we reflect on how these headsets might facilitate more immersive augmented TV viewing experiences within reach of consumers

THE INFORMATION TECHNOLOGY INTERACTION MODEL: A CORE MODEL FOR THE MBA CORE COURSE

This paper presents a teaching model we have used successfully in the MBA core course in Information Systems at several universities. The model is referred to as the "Information Technology Interaction Model" because it maintains that the consequences of information systems in organizations follow largely from the interaction of the technology with the organization and its environment. The model serves a number of pedagogical purposes: to integrate the various course components, to provide a formal foundation for the course content, to foster practical analytical skills, and to provide a framework for case discussions and student projects. Moreover, the model is intended to acquaint students with the dynamics of information systems in organizations and to help them recognize the benefits, dangers, and limitations of these systems. The paper includes a discussion and examples of how the model can be used for proactive and reactive analyses, and it concludes with an assessment of the model's effectiveness in the core course.Information Systems Working Papers Serie

A Spitzer Study of the Mass Loss Histories of Three Bipolar Pre-Planetary Nebulae

We present the results of far-infrared imaging of extended regions around three bipolar pre-planetary nebulae, AFGL 2688, OH 231.8+4.2, and IRAS 16342$-$3814, at 70 and 160 $\mu$m with the MIPS instrument on the Spitzer Space Telescope. After a careful subtraction of the point spread function of the central star from these images, we place constraints on the existence of extended shells and thus on the mass outflow rates as a function of radial distance from these stars. We find no apparent extended emission in AFGL 2688 and OH 231.8+4.2 beyond 100 arcseconds from the central source. In the case of AFGL 2688, this result is inconsistent with a previous report of two extended dust shells made on the basis of ISO observations. We derive an upper limit of $2.1\times10^{-7}$ M$_\odot$ yr$^{-1}$ and $1.0\times10^{-7}$ M$_\odot$ yr$^{-1}$ for the dust mass loss rate of AFGL 2688 and OH 231.8, respectively, at 200 arcseconds from each source. In contrast to these two sources, IRAS 16342$-$3814 does show extended emission at both wavelengths, which can be interpreted as a very large dust shell with a radius of $\sim$ 400 arcseconds and a thickness of $\sim$ 100 arcseconds, corresponding to 4 pc and 1 pc, respectively, at a distance of 2 kpc. However, this enhanced emission may also be galactic cirrus; better azimuthal coverage is necessary for confirmation of a shell. If the extended emission is a shell, it can be modeled as enhanced mass outflow at a dust mass outflow rate of $1.5\times10^{-6}$ M$_\odot$ yr$^{-1}$ superimposed on a steady outflow with a dust mass outflow rate of $1.5\times10^{-7}$ M$_\odot$ yr$^{-1}$. It is likely that this shell has swept up a substantial mass of interstellar gas during its expansion, so these estimates are upper limits to the stellar mass loss rate.Comment: 31 pages, 12 figures, accepted to A

Dynamic localization of yeast Fus2p to an expanding ring at the cell fusion junction during mating

Fus2p is a pheromone-induced protein associated with the amphiphysin homologue Rvs161p, which is required for cell fusion during mating in Saccharomyces cerevisiae. We constructed a functional Fus2p–green fluorescent protein (GFP), which exhibits highly dynamic localization patterns in pheromone-responding cells (shmoos): diffuse nuclear, mobile cytoplasmic dots and stable cortical patches concentrated at the shmoo tip. In mitotic cells, Fus2p-GFP is nuclear but becomes cytoplasmic as cells form shmoos, dependent on the Fus3p protein kinase and high levels of pheromone signaling. The rapid cytoplasmic movement of Fus2p-GFP dots requires Rvs161p and polymerized actin and is aberrant in mutants with compromised actin organization, which suggests that the Fus2p dots are transported along actin cables, possibly in association with vesicles. Maintenance of Fus2p-GFP patches at the shmoo tip cortex is jointly dependent on actin and a membrane protein, Fus1p, which suggests that Fus1p is an anchor for Fus2p. In zygotes, Fus2p-GFP forms a dilating ring at the cell junction, returning to the nucleus at the completion of cell fusion

Modifier loci condition autoimmunity provoked by Aire deficiency

Loss of function mutations in the autoimmune regulator (Aire) gene in autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy patients and mutant mice lead to autoimmune manifestations that segregate as a monogenic trait, but with wide variation in the spectrum of organs targeted. To investigate the cause of this variability, the Aire knockout mutation was backcrossed to mice of diverse genetic backgrounds. The background loci strongly influenced the pattern of organs that were targeted (stomach, eye, pancreas, liver, ovary, thyroid, and salivary gland) and the severity of the targeting (particularly strong on the nonobese diabetic background, but very mild on the C57BL/6 background). Autoantibodies mimicked the disease pattern, with oligoclonal reactivity to a few antigens that varied between Aire-deficient strains. Congenic analysis and a whole genome scan showed that autoimmunity to each organ had a distinctive pattern of genetic control and identified several regions that controlled the pattern of targeting, including the major histocompatibility complex and regions of Chr1 and Chr3 previously identified in controlling type 1 diabetes

Absolute diffuse calibration of IRAC through mid-infrared and radio study of HII regions

We investigate the diffuse absolute calibration of the InfraRed Array Camera on the Spitzer Space Telescope at 8.0microns using a sample of 43 HII regions with a wide range of morphologies near GLON=312deg. For each region we carefully measure sky-subtracted,point-source- subtracted, areally-integrated IRAC 8.0-micron fluxes and compare these with Midcourse Space eXperiment (MSX) 8.3-micron images at two different spatial resolutions, and with radio continuum maps. We determine an accurate median ratio of IRAC 8.0-micron/MSX\8.3-micron fluxes, of 1.55+/-0.15. From robust spectral energy distributions of these regions we conclude that the present 8.0-micron diffuse calibration of the SST is 36% too high compared with the MSX validated calibration, perhaps due to scattered light inside the camera. This is an independent confirmation of the result derived for the diffuse calibration of IRAC by the Spitzer Science Center (SSC). From regression analyses we find that 843-MHz radio fluxes of HII regions and mid-infrared (MIR) fluxes are linearly related for MSX at 8.3-microns and Spitzer at 8.0 microns, confirming the earlier MSX result by Cohen & Green. The median ratio of MIR/843-MHz diffuse continuum fluxes is 600 times smaller in nonthermal than thermal regions, making it a sharp discriminant. The ratios are largely independent of morphology up to a size of ~24 arcsec. We provide homogeneous radio and MIR morphologies for all sources. MIR morphology is not uniquely related to radio structure. Compact regions may have MIR filaments and/or diffuse haloes, perhaps infrared counter- parts to weakly ionized radio haloes found around compact HII regions. We offer two IRAC colour-colour plots as quantitative diagnostics of diffuse HII regions.Comment: 29 pages, LaTeX (aastex), incl. 31 PostScript (ps,eps) figures and 5 tables. Accepted by MNRAS (main journal). Replaced an unused file and added this URL for people wishing to download a version with high-resolution images: http://www.astro.wisc.edu/sirtf/martin.hii.accepted.pd