46 results on '"Waldron, Brian"'
Search Results
2. Stories of a water-table: anomalous depressions, aquitard breaches and seasonal implications, Shelby County, Tennessee, USA
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Lozano-Medina, Daniela, Waldron, Brian, Schoefernacker, Scott, Antipova, Anzhelika, and Villalpando-Vizcaino, Rodrigo
- Published
- 2023
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3. Determination of Contaminant Transport Parameters for a Local Aquifer by Numerical Modeling of Two Plumes: Trichloroethylene and Hexavalent Chromium.
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Ibn Salam, Mahade, Waldron, Brian, Schoefernacker, Scott, and Jazaei, Farhad
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HEXAVALENT chromium ,GROUNDWATER pollution ,PARAMETER estimation ,GROUNDWATER flow ,AQUIFERS - Abstract
The municipal wellfield in Collierville, Tennessee, is contaminated with trichloroethylene (TCE) and hexavalent chromium (Cr (VI)) due to industrial operations dating back to the 1970s and 1980s. This study aims to elucidate the aquifer's contaminant transport mechanisms by determining longitudinal and transverse dispersivities through inverse modeling. Utilizing MT3DMS for contaminant transport simulation, based on a well-calibrated groundwater flow model, and leveraging Python's multiprocessing library for efficiency, the study employs a trial-and-error methodology. Key findings reveal that longitudinal dispersivity values range from 5.5 m near the source to 20.5 m further away, with horizontal and vertical transverse dispersivities between 0.28 m and 3.88 m and between 0.03 m and 0.08 m, respectively. These insights into the aquifer's dispersivity coefficients, which reflect the scale-dependent nature of longitudinal dispersivity, are crucial for optimizing remediation strategies and achieving cleanup goals. This study underscores the importance of accurate parameter estimation in contaminant transport modeling and contributes to a better understanding of contaminant dynamics in the Collierville wellfield. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Hard edges, soft edges, and species range evolution: A genomic analysis of the Cumberland Plateau salamander.
- Author
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Watts, Emily F., Waldron, Brian P., and Kuchta, Shawn R.
- Abstract
Aim Location Taxon Methods Results Main Conclusions Gene flow from central to edge populations is thought to limit population growth at range edges by constraining local adaptation. In this study, we explore the thesis that range edges can differ in their dynamics and be either ‘hard’ (e.g. a river) or ‘soft’ (e.g. ecological gradients). We hypothesize that soft edge populations will have smaller effective population sizes than central populations and that gene flow will be greater from the centre to the edge than vice versa. Conversely, we hypothesize that hard edge populations should have similar effective population sizes to central populations and that gene flow will be equal between the two.Kentucky, West Virginia, and Virginia, USA.Plethodon kentucki (Caudata: Plethodontidae).We evaluated landscape suitability using an ecological niche model, then we compared gene flow and effective population sizes between edge and central populations and quantified gene flow between populations. Finally, we characterized landscape genetic variation, testing for isolation by distance and isolation by environment.We found continuously decreasing habitat quality along soft edges, with hard edges more variable. Additionally, we found that soft edges had lower effective population sizes than central populations and that gene flow was greater from the centre of the range to the soft edges than the reverse. In hard edges, by contrast, we found effective population sizes in edge populations were similar to central populations, with relatively equal gene flow in both directions.Understanding why species have range limits is central to investigations of the structure of biodiversity, yet the evolutionary dynamics of range edges remain poorly understood. We show that within a single species with a small range, the evolutionary dynamics operating at range boundaries may depend on the nature of the boundary. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Cryptic Species within a Cryptic Species? Species Delimitation in the Cumberland Plateau Salamander, Plethodon kentucki.
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Watts, Emily F., Waldron, Brian P., Hantak, Maggie M., Lemmon, Emily Moriarty, Lemmon, Alan R., and Kuchta, Shawn R.
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PHYLOGEOGRAPHY , *SALAMANDERS , *GENETIC variation , *SPECIES , *SPECIES distribution , *GENE flow - Abstract
The Cumberland Plateau Salamander, Plethodon kentucki, is a cryptic species with respect to the sympatric Northern Slimy Salamander, Plethodon glutinosus. It was first described by Highton and MacGregor (1983) by using allozyme data. In that description, the authors reported extreme levels of genetic differentiation for a single species with a narrow distribution; however, follow-up studies found patterns of genetic variation that were discordant with the allozyme data. In this paper, we describe patterns of genetic variation within P. kentucki by using an anchored hybrid enrichment dataset of 21 individuals sampled from across its known range. We identified four genetic groups with extensive admixture and isolation by distance. We constructed a population tree by using TreeMix and inferred gene flow between two of the four genetic groups. Finally, we used Bayesian phylogenetics and phylogeography (BPP) in conjunction with the genealogical divergence index (gdi) to test species boundaries within P. kentucki. Although BPP suggested that P. kentucki could be four species, gdi indicated that none of the groups were sufficiently independent to constitute separate species. We conclude that P. kentucki is best recognized as a single species with substantial genetic structure within its limited distribution. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Population Structure and Species Delimitation in the Wehrle's Salamander Complex.
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Kuchta, Shawn R., Waldron, Brian P., Watts, Emily F., Lemmon, Alan R., and Lemmon, Emily Moriarty
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SALAMANDERS , *GENETIC variation , *SINGLE nucleotide polymorphisms , *SPECIES , *GENE flow - Abstract
Species are the fundamental unit of biodiversity studies. However, many species complexes are difficult to delimit, especially those characterized by complicated patterns of population structure. Salamanders in the family Plethodontidae often form species by slowly fragmenting across a landscape over space and time. They thus provide many examples of species complexes in which gradual Darwinian evolution has resulted in multiple units of varying degrees of differentiation, including incompletely separated lineages. Herein, we report on a molecular systematic investigation of woodland salamanders in the Plethodon wehrlei group, a group that has recently been split from two species into five species. To quantify patterns of genetic variation, we collected genetic samples from 24 individuals from 20 populations, including all species and representing a carefully selected subset of previous work. From these samples, we obtained genomic data by using anchored hybrid enrichment, resulting in 319 loci averaging 1300 bp in length. Biallelic single-nucleotide polymorphisms were randomly selected from 316 of these loci for some analyses. We examined patterns of genetic structure by using a combination of multivariate statistics and methods based on evolutionary models (such as the Bayesian program STRUCTURE) and found that all of the recognized species formed genetic clusters; however, P. wehrlei and P. punctatus were relatively weakly differentiated and STRUCTURE identified three separate clusters within P. jacksoni. Species trees inferred using the weighted accurate species tree algorithm (wASTRAL), Bayesian phylogenetics and phylogeography (BPP), and TreeMix all recovered the same topology, with P. dixi sister to the other taxa, which included a northern clade (P. wehrlei, P. punctatus, P. pauleyi) and a southern clade (P. jacksoni, with three separate groups). TreeMix only inferred one gene flow event. We evaluated the candidate species by using BPP and the genealogical divergence index (gdi). Although BPP delimited all candidate species with strong support (all posterior probabilities = 1.0), the gdi only strongly supported P. dixi and P. pauleyi, both of which have only been recently described. We discuss the difficult problem of species delimitation in groups that form species via range fragmentation. We also provide a vision for future research, with the aim of better testing and diagnosing the species diversity within the P. wehrlei group. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Traversing the Great Lakes: Post‐glacial colonization by a widespread terrestrial salamander.
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Waldron, Brian P., Watts, Emily F., and Kuchta, Shawn R.
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Aims Location Taxon Methods Results Main Conclusions Glacial retreat at the end of the Pleistocene epoch opened vast expanses of emergent habitat in the northern hemisphere that were colonized by opportunistic taxa. However, species that undergo post‐glacial expansion may have originated from one or several glacial refugia. We inferred the post‐glacial expansion history of the Eastern Red‐backed Salamander (Plethodon cinereus), a fully terrestrial species with a vast distribution despite severe dispersal limitations. Previous studies indicated populations south of the glacial boundary at the eastern and western limits of the distribution were closely related, suggesting either multiple refugia or an extraordinary post‐glacial expansion event.Eastern North America.Plethodon cinereus (Green, 1818), Caudata: Plethodontidae.We collected ddRAD‐seq data from 106 individuals throughout the distribution of P. cinereus. We estimated phylogeographic structure, including finer‐scale structure among the post‐glacial populations. To test the origins and routes of colonization, we used ecological niche modelling, population trees and analyses of directional range expansion.Analyses supported our hypothesis of a southeastern glacial refugium, with northward expansion along the Eastern Seaboard prior to westward invasion into the Great Lakes region, including southwestern expansion into unglaciated areas at the western end of the distribution. However, a distinct subgroup in the northwestern portion of the range raises the possibility of a second refugium near the ice‐free Driftless Area.Based on our results, we hypothesize a southeastern refugium from which most of today's northern populations undertook extensive post‐glacial colonization. Our results indicate a geographically non‐linear colonization history for P. cinereus. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Recharge pathways and rates for a sand aquifer beneath a loess-mantled landscape in western Tennessee, U.S.A.
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Larsen, Daniel, Bursi, John, Waldron, Brian, Schoefernacker, Scott, and Eason, James
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- 2020
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9. Genetic Analysis of a Cryptic Contact Zone between Mitochondrial Clades of the Eastern Red-Backed Salamander, Plethodon cinereus
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Waldron, Brian P., Kuchta, Shawn R., Hantak, Maggie M., Hickerson, Cari-Ann M., and Anthony, Carl D.
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- 2019
10. Assessing water distribution and agricultural expansion in the Cele Oasis, China
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Waldron, Brian, Gui, Dongwei, Liu, Yi, Feng, Lydia, and Dai, Heng
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- 2020
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11. Wellfield optimization to minimize contaminant migration from a surficial to a semi‐confined aquifer using numerical modeling.
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Paul, Sondipon, Waldron, Brian, Jazaei, Farhad, and Larsen, Daniel
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AQUIFERS , *WATER pollution , *LIFE expectancy , *GROUNDWATER - Abstract
The shallow, Memphis, and Fort Pillow aquifers are the three major water‐bearing strata beneath Memphis, Tennessee, where the Memphis aquifer serves as the primary groundwater source. The upper Claiborne confining unit (UCCU) separates shallow and Memphis aquifers across the majority of Shelby County, acting as an upper protective layer for the Memphis aquifer. However, hydrogeologic breaches within the UCCU create a hydraulic connection and provide an avenue for potential contaminant migration from the shallow to the Memphis aquifer. This research aims to minimize contaminant migration, mitigate risks, extend existing wells' life that may face water contamination, and find suitable locations for future well construction. Several strategies are developed addressing well depth, seasonal well operation, and mapping no‐drilling or red zones to provide practical solutions. A numerical groundwater modeling technique is developed for each strategy that includes stochastic simulation–optimization and customized simulation models depending on the strategy. The models result in thousands of numerical simulations for each scenario to identify recurring patterns of contaminant movement to and through the Memphis aquifer. The results indicate that optimum well positions (spatially and vertically) and modification to pumping can increase the life expectancy of wellfields, offer sustainable management of the Memphis aquifer, and reduce contaminant migration through 2050. [ABSTRACT FROM AUTHOR]
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- 2023
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12. Manual Sensitivity Analysis to Enhance a Previously PEST-Calibrated Shallow Aquifer and Aquitard Breach Model.
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Pierce, Joel, Waldron, Brian, and Jazaei, Farhad
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AQUIFERS ,SENSITIVITY analysis ,HYDROGEOLOGICAL modeling ,ELECTRIC batteries ,WATER table ,CONCEPTUAL models ,EVAPOTRANSPIRATION - Abstract
Numerical groundwater modelers often encounter challenges in computing and implementing regional unconfined aquifer models that match real-world water table undulations and local features. A commonly-practiced simplifying assumption in groundwater models states that incorporating extensive real-world detail does not correlate to better model results. This study discusses how this assumption may lead to unrepresentative models due to oversimplification. Sometimes, when determining the appropriate complexity of regional models, important elements of the conceptual model may be oversimplified, resulting in a nonrepresentative model or part of a model. This study tests the hypothesis that, by incorporating specific areas of greater hydrogeologic complexity into modeling a regional-sized unconfined aquifer, simulated heads will significantly better match observed conditions, especially in areas where unconfined groundwater discharges through aquitard breaches and where dry cells are a natural (realistic) condition of the system. Three surface processes (additional recharge, stream density, and evapotranspiration) were tested in multiple sets of impact models. Model outcomes were compared against observed conditions of the shallow unconfined aquifer beneath Memphis, TN, US, and against the parent fully calibrated groundwater model of the aquifer systems beneath Shelby County, TN. Results indicate that an increase in stream detail better mimics observed water table undulations. These undulations occur at the same scale as aquitard breaches and improve appropriate gradients and flow surrounding the breaches. Results further indicate that the addition of greater hydrogeologic complexity to the shallow unconfined aquifer improves models like that of Shelby County, TN, by better representing realistic gradients, conveying appropriate quantities of water through breaches, and offering an opportunity for improved contaminant transport modeling from the shallow unconfined aquifer to the deeper semiconfined Memphis aquifer via aquitard breaches. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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13. Identification of Breaches in a Regional Confining Unit Using Electrical Resistivity Methods in Southwestern Tennessee, USA.
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Hasan, Md Rizwanul, Larsen, Daniel, Schoefernacker, Scott, and Waldron, Brian
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AQUIFERS ,EOCENE Epoch ,ELECTRICAL resistivity ,WATER supply ,SENSITIVITY analysis - Abstract
Electrical resistivity and borehole data are applied to delineate lithostratigraphic boundaries and image the geometry of confining-unit breaches in Eocene coastal-plain deposits to evaluate inter-aquifer exchange pathways. Eight dipole–dipole array surveys were carried out, and apparent resistivity was inverted to examine the lateral continuity of lithologic units in different water-saturation and geomorphic settings. In addition, sensitivity analysis of inverted resistivity profiles to electrode spacing was performed. Resistivity profiles from Shelby Farms (SF) highlight the effect of varied electrode spacing (2.5, 5, and 10 m), showing an apparent ~0.63 to 0.75 depth shift in resistivity-layer boundaries when spacing is halved, with the 10 m spacing closely matching borehole stratigraphy. Grays Creek and Presidents Island profiles show clay-rich Eocene Cook Mountain Formation (CMF), with resistivity ranging from 10 to 70 Ω-m, overlying the Eocene Memphis Sand—a prolific water-supply aquifer. Resistivity profiles of SF and Audubon Park reveal sandy Cockfield Formation (CFF) paleochannels inset within and through the CMF, providing hydrogeologic connection between aquifers, and clarifying the sedimentary origin of confining-unit breaches in the region. The results underscore the efficacy of the electrical resistivity method in identifying sand-rich paleochannel discontinuities in a low-resistivity regional confining unit, which may be a common origin of breaches in coastal-plain confining units. [ABSTRACT FROM AUTHOR]
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- 2023
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14. Repeatability of foraging behavior following a simulated predation attempt depends on color morph, sex, and foraging metric in Red-backed salamanders (Plethodon cinereus).
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Waldron, Brian P., Ganzfried, Marissa C., Hickerson, Cari-Ann M., and Anthony, Carl D.
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PREDATION , *FORAGING behavior , *SALAMANDERS , *STATISTICAL reliability , *FOREST litter - Abstract
Behavioral repeatability greatly affects the capacity of an individual to respond to varying environments. When multiple behaviors within individuals are repeatable and correlated across time or across contexts, it is termed a behavioral syndrome. However, not all behaviors exhibit the same level of repeatability, and relatively few studies have examined repeatability in amphibians. We examined the repeatability of foraging behavior in the Eastern Red-backed salamander (Plethodon cinereus), a color-polymorphic terrestrial salamander, following a simulated predation attempt. We tested several hypotheses: (1) Simulated predation would negatively affect foraging, increasing latency to feed and decreasing the number of prey items eaten in a fixed time period compared to a control group; (2) Because striped color morphs of P. cinereus are more aggressive, striped individuals would exhibit "bold" behavior by resuming foraging sooner and consuming more prey; and (3) Foraging behavior would be more repeatable for males. We found that the predation treatment inhibited foraging behavior, although neither morphs nor sexes differed in either forging metric. The number of prey eaten was repeatable for all groups of salamanders. Latency to feed, however, was not repeatable for control salamanders. Simulated predation induced repeatable latencies, but when morphs and sexes were analyzed separately, only unstriped and male salamanders were repeatable, suggesting characteristics of these groups related to behavioral syndromes drive this response. We speculate that the greater repeatability of the unstriped morph's latency to feed may result from more frequent encounters with predators in the leaf litter matrix while foraging. Striped salamanders from the source population, in turn, exhibit greater territorial success, and thus may experience more variation in encounters with predators and conspecifics over the course of their lifespans. Our results illustrate the need to carefully define the behavior and subset of the population to be tested when studying behavioral repeatability or behavioral syndromes. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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15. Characterization of Hydraulic Properties of the Memphis Aquifer by Conducting Pumping Tests in Active Well Fields in Shelby County, Tennessee.
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Sahagún‐Covarrubias, Sofía, Waldron, Brian, Larsen, Daniel, and Schoefernacker, Scott
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AQUIFERS , *DATA analysis , *GROUNDWATER , *COUNTIES - Abstract
Limited availability of field measurements for aquifer parameters commonly leads to nonuniqueness of numerical model solutions. Six pumping tests were conducted in five municipal well fields within Shelby County following the procedure described in the ASTM D4050‐14 and using an additional qualitative matrix framework to achieve greater reliability. Drawdown data of the pumping tests were analyzed using AQTESOLV, which allowed for partial penetration of well screens and interference from neighboring production wells. The values of transmissivity have a combined range of 600–3,100 m2/day, which is 2–4 times less than published measures that used less robust data analysis and questionable or poorly documented methods. The range of storativity was 0.0005–0.002, and again, the resulting values have greater reliability than prior investigations. Robust quality assessment in the present methodology through assignment of a scoring decision matrix provides greater trust in the measurements. With a score at or above 10 considered optimal, the methodology and test environment resulted in an average score of 8.7, a vast improvement from prior investigations that together averaged 4.1. The calculated parameter values are an improvement on historical values, constraining the two critical groundwater hydraulic terms that should reduce modeling nonuniqueness of numerical modeling solutions that should lead to improved evaluation of local groundwater resources and environmental impacts. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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16. Family planning and inflammatory bowel disease: the patient and the practitioner
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Toomey, Desmond and Waldron, Brian
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- 2013
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17. Complete Streets: A New Capability Maturity Model.
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Jordan, Samuel W., Ivey, Stephanie, Levy, Marian, Lipinski, Martin, Palazolo, Paul, and Waldron, Brian
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CAPABILITY maturity model ,CAPACITY building ,STRATEGIC planning - Abstract
Complete Streets (CS) practice in the United States is heterogeneous. While organizations like the National Complete Streets Coalition have offered guidance on the formation of a robust Complete Streets policy, the maturity of public programs for Complete Streets practice is ill-defined. This research adapts existing transportation-focused capability maturity frameworks to propose a new capability maturity model for Complete Streets that is designed to help organizations evaluate current program maturity and identify next steps for evolving practice. The model includes a self-assessment tool and a set of qualitative descriptions of incrementally increasing maturity across seven program dimensions determined to be fundamental to the success of Complete Streets programs. The proposed model is designed to assist in strategic planning and organizational capacity building. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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18. Groundwater–surfacewater interactions at the transition of an aquifer from unconfined to confined
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Urbano, Lensyl, Waldron, Brian, Larsen, Dan, and Shook, Heather
- Published
- 2006
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19. Application of Numerical Groundwater Model to Determine Spatial Configuration of Confining Unit Breaches near a Municipal Well Field in Memphis, Tennessee.
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Torres-Uribe, Hugo E., Waldron, Brian, Larsen, Daniel, and Schoefernacker, Scott
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THREE-dimensional flow ,HYDRAULIC conductivity ,GROUNDWATER flow ,GROUNDWATER ,WATER supply - Abstract
Thinning or localized absence (a breach) of an aquitard warrant concern because this limits the protection it affords water-supply aquifers beneath. The objective of this study was to assess potential spatial configurations of breaches within the aquitard overlying a water-supply aquifer in an urban well field. A three-dimensional groundwater flow model was utilized to investigate leakage pathways through the aquitard and simulate five potential breach configurations with three different hydraulic conductivity values. Through particle tracking analysis, estimates for the modern water percentage and apparent age of the modern water extracted by the production wells at the well field were obtained and compared to published age-dating data. Breach configurations resembling a broad paleochannel, which could originate through erosion of clay and silt within the aquitard, match the extent and proportion of modern water in the water-supply aquifer at the well field. This methodology has utility in evaluating the vulnerability of water-supply aquifers that are partially confined and susceptible to contamination, while assessing the likelihood of potential zones of increased vulnerability and offering targets for further investigations. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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20. Groundwater well optimization to minimize contaminant movement from a surficial shallow aquifer to a lower water supply aquifer using stochastic simulation-optimization modeling techniques: Strategy formulation
- Author
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Paul, Sondipon, Waldron, Brian, Jazaei, Farhad, Larsen, Daniel, and Schoefernacker, Scott
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- 2022
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21. Urban effects on flood plain natural hazards: Wolf River, Tennessee, USA
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Yates, Rhonda, Waldron, Brian, and Van Arsdale, Roy
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- 2003
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22. 'Lonely in my head': The experiences of loneliness in individuals with brain injury.
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Lowe, Niamh, Crawley, Lorraine, Wilson, Charlotte, and Waldron, Brian
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BRAIN injuries ,LONELINESS ,SOCIAL isolation ,THEMATIC analysis ,HEALING - Abstract
Primary objective: This paper reports on the personal experiences of loneliness for individuals living with brain injury. Research design: This is a qualitative research design, employing semi‐structured interviews and subsequent contextualist thematic analysis. Methods and procedures: Eleven clients (two female and nine male, aged between 27 and 63 years) with brain injury participated in semi‐structured interviews. Thematic analysis was employed in the interpretation of the data. Main outcomes and results: The interview data and subsequent analysis depicted three overarching themes in a healing process – 'Internal Loneliness', 'Healing the Cracks', and 'Visible with Cracks'. Participants described five factors which contribute to their feeling of loneliness: trauma, social isolation, concealment, rejection of part of self, and invisibility of their disability. The participants' accounts also detailed the necessity of a therapeutic intervention and relationship to deal with and address some of these issues. Conclusions: This study highlights that processing the trauma, developing dialectical thinking, self‐compassion, and a degree of self‐acceptance assist in the movement of participants towards allowing themselves to be 'Visible with Cracks'. This allowance of self to be fully seen appears to serve an important function for reconnection with self and others. These results may help to inform brain injury rehabilitative care, through developing their understanding of the internal loneliness factors that may be influencing an individual's social isolation or social withdrawal. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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23. Caregiver burden & distress �in families with ABI in Ireland
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Waldron, Brian and Behan, Joanne
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- 2017
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24. Attempted suicide leading to acquired brain injury: a scoping review.
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Higgins, Ciara, Rooney, Katy, O'Connell, Barbara, Waldron, Brian, and Linehan, Christine
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BRAIN injuries ,DISEASES ,NEEDS assessment ,SUICIDAL behavior ,SYSTEMATIC reviews ,LITERATURE reviews ,SOCIAL support ,SEVERITY of illness index ,REHABILITATION for brain injury patients - Abstract
Objective: Conduct a scoping review of literature surrounding acquired brain injury (ABI) sustained secondary to a suicide attempt to establish the current body of research on injury outcomes and rehabilitative needs for this population. Methods: A systematic search of the literature was conducted. Searches were conducted using terms relating to this injury etiology and search results with original or secondary data on individuals with an ABI were included for review. Results: Thirty-two articles were reviewed. Limited data characterizing this population exists in the literature. Findings indicate that this population have generally poorer injury outcomes compared with ABI sustained through other means. Rehabilitative needs are rarely addressed, but limited commentary suggests that extensive pre-morbid conditions, severity of injuries and psychosocial support needs of this population present implications for rehabilitative supports. Conclusion: There is a relative dearth of research examining ABI sustained secondary to a suicide attempt. Collated findings suggest these individuals are rarely recognized in the literature as a distinct ABI population with rehabilitative needs specific to this etiology. Future research should aim to address the gaps identified in the literature, including characterizing the population, establishing pre-morbid conditions and developing tailored rehabilitative support to address complex needs. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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25. Low-level soluble chloride extraction in soil
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Larsen, Daniel and Waldron, Brian
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- 2020
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26. Breakeven Evaluation of Irrigation System in Tennessee
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Pasaribu, Katryn, He, Lixia L., Boyer, Christopher N., Lambert, Dayton M., English, Burton C., Clark, Christopher D., Lieb, Brain, and Waldron, Brian
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Production Economics ,Corn ,Farm Management ,Breakeven Price ,Cotton ,Soybean ,Irrigation ,Simulation - Abstract
Conflict over water use in the southeastern US is increasingly common as communities and industries fund themselves without adequate water supplies. However, agricultural water use in the southeastern states has received relatively little attention despite rapid growth in the use of irrigation by the region’s farmers. This study determines the breakeven prices for dryland and irrigated crops produced in the Tennessee River Basin and Hiwassee-Mississippi watersheds. The analysis focuses on five major crops produced in the region: corn, soybean, cotton, wheat and sorghum. Tillage practices considered are conventional, reduced, and no-till. Irrigation technologies include furrows, center pivot, and big-gun/traveler systems. Water sources include surface and wells. Center pivot systems are currently the dominant irrigation practice in the region. We hypothesize that gravity-based systems are more profitable under certain conditions. Well installation costs largely determine the profitability of irrigation practices in the study area. Key differences will be driven by the relative price of commodities, the production portfolio of producers, and energy, labor, and installation costs. Repair expenses for irrigation systems are insensitive to different well depths, but sensitive to the type of irrigation system implemented. These findings will be useful for producers augmenting their operations with irrigation systems.
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- 2016
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27. Emergency surgery in octogenarians: Outcomes and factors affecting mortality in the general hospital setting.
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Bolger, Jarlath C., Zaidi, Akif, Fuentes-Bonachera, Adrian, Kelly, Michael E., Abbas, Aqeel, Rogers, Ailin, McCormack, Tom, Waldron, Brian, and Murray, Kevin P.
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HERNIA surgery ,ABDOMINAL surgery ,ELDER care ,LENGTH of stay in hospitals ,HOSPITAL admission & discharge ,HOSPITAL emergency services ,INTENSIVE care units ,MULTIVARIATE analysis ,PATIENTS ,SURGEONS ,OPERATIVE surgery ,EMPLOYEES' workload ,TREATMENT effectiveness ,RETROSPECTIVE studies ,OLD age - Abstract
Aim: The Western world has an expanding older population, who are living longer with increasing numbers of comorbidities. In addition, expectations of patients and relatives are increasing. As a general hospital operating in a rural setting, our University Hospital Kerry, Tralee, Ireland, deals with a significant number of emergency presentations to the acute surgical service. The aim of the present study was to examine outcomes for patients in the extremes of age who present requiring emergency surgical procedures. Methods: A retrospective review of theater and admission logs was carried out to identify all emergency surgeries from January 2008 to December 2015. All patients aged >80 years at the time of surgery were identified. Details of surgery were recorded, in addition to biochemical and hematological data, use of intensive care unit, length of stay and mortality. Results: In total, 128 octogenarians underwent an emergency surgery. The average patient age was 84.3 years (range 80-94 years). The commonest procedures were laparotomy (65%, n = 84), repair of strangulated/incarcerated hernia (18%, n = 23) and laparoscopic procedures (16%, n = 21). The 30-day all-cause mortality was 22.6%. On multivariate analysis, American Society of Anesthesia status and intensive care unit utilization predicted mortality (P = 0.04 and 0.05, respectively). A total of 82 patients required intensive care unit admission, with an average length of stay of 4.8 days, using 484 bed days in total. Conclusions: Emergency surgery in octogenarians is a significant part of the workload of general surgeons. Poor baseline status is associated with an increased risk of mortality. Emergency surgery in older adults only utilizes a fraction of available intensive care unit resources. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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28. Tyranny and cruelty.
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Waldron, Brian J.
- Abstract
Presents a case study of a asthmatic patient by her physician, also an asthmatic. What an asthmatic attack is like; Causes; How asthma's prevalence is on the rise; Treatment; Potency of anti-asthma agents.
- Published
- 1993
29. Muscle Tones
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Waldron, Brian J.
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Osteopathy ,Dystonia ,Science and technology - Abstract
http://discovermagazine.com/1997/jan/muscletones1051
- Published
- 1997
30. LITE Flood: Simple GIS-Based Mapping Approach for Real-Time Redelineation of Multifrequency Floods.
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Javadnejad, Farid, Waldron, Brian, and Hill, Arleen
- Subjects
FLOOD risk ,FLOOD insurance rates ,GEOGRAPHIC information systems ,REAL-time computing ,CARTOGRAPHY - Abstract
Flood zones with 1 and 0.02% of annual flooding chance are projected in FEMA's digital flood insurance rate maps (DFIRMs) and are suited for identifying flood risk at the largest impacts. However, less severe floods, which are not mapped in DFIRMs, still cause significant damage and occur on a more frequent basis. This article uses a simplified rapid geographic information system (GIS)-based solution for on-thefly inundation mapping of small flood events. The linear interpolation technique (LITE Flood) was developed to approximate the prone flood zones based on river stage without performing additional hydraulic simulations. The approach was evaluated by comparing the results to the corresponding storm scenarios simulated in a standard river hydraulics simulator. The case study is a portion of Wolf River and its two main tributaries in Shelby County, which is located in the southwest corner of Tennessee. The stream channelization of the lower portion ofWolf River has mitigated large flood events, while causing frequent flooding from less severe storms. LITE Flood produced results with good to acceptable accuracy. LITE Flood can be used for rapid, cost-effective, and real-time mapping of multifrequency floods at a large scale, thereby aiding local community emergency response agencies who often do not have the expertise to perform more sophisticated hydraulic modeling but do have a GIS capacity. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
31. Application of Environmental Tracers in the Memphis Aquifer and Implication for Sustainability of Groundwater Resources in the Memphis Metropolitan Area, Tennessee.
- Author
-
Larsen, Daniel, Waldron, Brian, Schoefernacker, Scott, Gallo, Haley, Koban, John, and Bradshaw, Elizabeth
- Subjects
- *
GROUNDWATER , *SUSTAINABILITY ,MEMPHIS Aquifer - Abstract
Fourteen years of results from environmental tracer sampling for 3H, He isotopes, noble gases, and SF6 in production wells screened in the Memphis aquifer in Memphis, Tennessee, are presented and used to determine the age and mass proportion of modern water (<60 years old) pumped from this regionally important public supply aquifer. The results indicate persistent presence of modern water in water pumped from one or more production wells in most of the well fields sampled. The percentage of modern water is quantified by three methods: tritium-loading history, inverse geochemical modeling, and lumped parameter modeling. The mixing percentages and ages determined from each technique are generally in agreement, but also emphasize the unique information provided by each tracer and associated modeling approaches. The implications of the tracer data for sustainability and vulnerability are also considered, especially in regard to potential water quality threats to the water supply in the Memphis, Tennessee, metropolitan area. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
32. Pre-Development Groundwater Conditions Surrounding Memphis, Tennessee: Controversy and Unexpected Outcomes.
- Author
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Waldron, Brian and Larsen, Daniel
- Subjects
- *
GROUNDWATER research , *GROUNDWATER pollution , *WATER table , *WATER supply - Abstract
Reliance on groundwater resources by differing governing bodies can create transboundary disputes raising questions of ownership and apportionment as the resource becomes strained through overuse or threatened by contamination. Transboundary disputes exist at varying scales, from conflicts between countries to smaller disputes between intrastate jurisdictions. In 2005 within the United States, the State of Mississippi filed a lawsuit against its political neighbor and their utility, the City of Memphis and Memphis Light, Gas, and Water, for groundwater deemed owned by the State of Mississippi to be wrongfully diverted across the state line and into Tennessee by the defendants. The basis of the lawsuit was potentiometric maps of groundwater levels for the Memphis aquifer that showed under suggested pre-development conditions no flow occurring across the Mississippi- Tennessee state line, but subsequent historic potentiometric maps show a cone of depression under the City of Memphis with a clear northwesterly gradient from Mississippi into Tennessee. The suggested pre-development conditions were derived from limited groundwater level observations between 41 and 74 years post-development. A new pre-development map is constructed using historic records that range 0-17 years post-development that shows the natural flow is northwesterly from Mississippi into Tennessee and transboundary groundwater quantities have actually decreased since pre-development conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
33. Quaternary deformation and fault structure in the Northern Mississippi Embayment as imaged by near-surface seismic reflection data.
- Author
-
Guo, Lei, Magnani, Maria Beatrice, McIntosh, Kirk, and Waldron, Brian
- Abstract
Seismicity in the New Madrid seismic zone (NMSZ) in the central United States constrains the location of present deformation at depth along four main distinct arms, while the surface expression of the ongoing deformation is still unclear. To better constrain the surface deformation in the NMSZ, we integrate existing seismic reflection data with a new ~300 km-long high-resolution seismic reflection profile acquired along the Mississippi River from Cape Girardeau, MO, to Caruthersville, MO. Based on the data, we interpret the Reelfoot Thrust and the New Markham Fault as upward splays of a blind master fault defined by the seismicity and extending at depth farther north. To the south, two faults, the Axial Fault and the Cottonwood Grove Fault, are imaged above the southern arm of the NMSZ. Both fault display deformation of the Paleozoic through the Tertiary sediments, and a relief of ~20-25 m at the base of the Quaternary alluvium, which we interpret as the result of strike-slip motion along a complex fault plane geometry. We propose two alternative interpretations for the relationship between the shallow faults and the seismicity in this area: (1) the faults merge at depth and are presently both active and (2) the faults are distinct at depth and were active during the Quaternary and only the Axial Fault is presently deforming. Geological structures mapped at the surface as part of this study show that Quaternary deformation is accommodated along a fault network that is more complex than the simple four-arm system illuminated by the seismicity, a behavior predicted by analog and computer models. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
34. A qualitative exploration of how individuals reconstruct their sense of self following acquired brain injury in comparison with spinal cord injury.
- Author
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Lennon, Aisling, Bramham, Jessica, Carroll, Àine, McElligott, Jacinta, Carton, Simone, Waldron, Brian, Fortune, Donal, Burke, Teresa, Fitzhenry, Mark, and Benson, Ciaràn
- Subjects
SPINAL cord injuries ,BRAIN injuries ,ADAPTABILITY (Personality) ,PSYCHOLOGICAL adaptation ,AUTONOMY (Psychology) ,COMPARATIVE studies ,INTERVIEWING ,LIFE change events ,LIFE skills ,PHENOMENOLOGY ,MEDICAL rehabilitation ,PATIENTS ,RESEARCH funding ,STATISTICAL sampling ,SELF-perception ,JUDGMENT sampling ,ACTIVITIES of daily living ,NARRATIVES ,THEMATIC analysis ,PSYCHOLOGY - Abstract
Primary objective: The present study aimed to investigate the specific ways in which individuals reconstruct their sense of self following injury to the nervous system, by comparing individuals with acquired brain injury (ABI) and individuals with spinal cord injury (SCI), two groups that have experienced a sudden-onset injury with life-changing repercussions. Research design: Phenomenological qualitative research. Methods and procedures: Nine individuals with ABI and 10 individuals with SCI took part in an interview exploring the ways in which individuals reconstruct their sense of self following injury. Data were analysed using interpretative thematic analysis. Main outcomes and results: Findings showed similar themes identified within the interview data of the ABI and SCI groups. Both groups developed positive and negative self-narratives. Individuals employed strategies that facilitated the reconstruction of positive self-narratives. In addition, individuals described their sense of self as simultaneously continuous and changing. Discussion: Findings are discussed in relation to proposed models of self-reconstruction post-injury to the nervous system. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. PLETHODON CINEREUS (Eastern Red-backed Salamander) and PLETHODON ELECTROMORPHUS (Northern Ravine Salamander).
- Author
-
WALDRON, BRIAN and HANTAK, MAGGIE
- Subjects
- *
SALAMANDERS , *LIFE sciences - Abstract
The article presents a report regarding the discovery and geographical distribution of Eastern Red-backed Salamander, Plethodon Cinereus and Northern Ravine Salamander, Plethodon Electromorphus.
- Published
- 2020
36. Cognitive behavioural therapy for depression and anxiety in adults with acquired brain injury. What works for whom?
- Author
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Waldron, Brian, Casserly, LisaMarie, and O'Sullivan, Clodagh
- Subjects
- *
COGNITIVE therapy , *MENTAL depression , *ANXIETY , *BRAIN injuries , *CEREBROVASCULAR disease , *HYPOXEMIA , *NEUROSURGERY , *ADULTS , *MENTAL health - Abstract
This paper reviews treatment outcome studies on cognitive behavioural therapy (CBT) for depression and anxiety following acquired brain injury (ABI), including traumatic brain injury (TBI), cerebral vascular accident (CVA), anoxia and neurosurgery. Studies are included for review when the published paper included an anxiety disorder or depression as the treatment focus, or as part of outcome measurement. Relaxed criteria were used to select studies including relevant single-cases, case series and single group studies along with studies that employed control groups. Twenty-four studies were identified. Twelve papers were of a single-case design (with or without replication). Two papers used uncontrolled single groups and ten studies used a control group. There were a total of 507 people in the various treatment and control groups, which ranged in size from 6 to 67 persons. All participants in the study had an ABI. Our review indicates CBT often shows a within-group pre- to post-treatment statistical difference for depression and anxiety problems, or a statistical difference between CBT-treated and non-treated groups. For studies that targeted the treatment of depression with CBT, effect-sizes ranged from 0 to 2.39 with an average effect-size of 1.15 for depression (large effect). For studies that targeted the treatment of anxiety with CBT, effect-sizes ranged from 0 to 3.47 with an average effect-size of 1.04 for anxiety (large effect). However, it was not possible to submit all twenty-four studies identified to effect-size analysis. Additionally, it is clear that CBT is not a panacea, as studies frequently indicate only partial reduction in anxiety and depression symptoms. This review suggests that if CBT is aimed at, for example, anger management or coping, it can be effective for anger or coping, but will not generalise to have an effect on anxiety or depression. CBT interventions that target anxiety and depression specifically appear to generate better therapeutic effects on anxiety and depression. Gaps in the literature are highlighted with suggestions for future research. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
37. Critical Role for Transient Receptor Potential Channel TRPM4 in Myogenic Constriction of Cerebral Arteries.
- Author
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Earley, Scott, Waldron, Brian J., and Brayden, Joseph E.
- Published
- 2004
- Full Text
- View/download PDF
38. Impact of River Channelization on Seismic Risk: Shelby County, Tennessee.
- Author
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Van Arsdale, Roy, Waldron, Brian, Ramsey, Natasha, Parrish, Shane, and Yates, Rhonda
- Subjects
STREAM channelization - Abstract
The lower 35.4 km of the Wolf River, in the city of Memphis, Shelby County, Tennessee, was channelized in 1964 to reduce flooding. Detailed channel surveys conducted in 1959 and 1990 document river and floodplain changes 26 years after channelization. Channelization resulted in a straighter, steeper, deeper, wider, and smoother channel, thus causing an increase in channel velocity, cross-sectional area, and discharge capacity. Subsequent to channelization, Wolf River became shallower near its mouth, entrenched 3 m in its upstream reach, and formed a nick point at the eastern end of the channelized reach that migrated 11.3 km upstream. Tributaries to the channelized segment of the Wolf River have also entrenched. In addition, the floodplain along the channelized reach underwent dissection and denudation and the banks of the Wolf River were an average of 1 m lower in elevation than they were in 1959. Channelization and subsequent river changes have reduced flooding in the channelized portion of the river as intended. However, negative consequences of these river changes include (1) costly bridge and pipeline repair, (2) river and wetlands habitat destruction, (3) probable increased susceptibility for earthquake liquefaction and associated lateral spreading of the Wolf River floodplain, and (4) increased earthquake risk due to building development on the Wolf River floodplain. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
39. Development of a Numerical Multi-Layered Groundwater Model to Simulate Inter-Aquifer Water Exchange in Shelby County, Tennessee.
- Author
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Villalpando-Vizcaino, Rodrigo, Waldron, Brian, Larsen, Daniel, and Schoefernacker, Scott
- Subjects
GROUNDWATER ,GROUNDWATER quality ,GEOLOGICAL surveys ,AQUIFERS ,COUNTIES - Abstract
Inter-aquifer water exchange between the shallow and Memphis aquifers in Shelby County, Tennessee may pose a contamination threat due to the downward migration of younger, poor quality groundwater into deeper, more pristine aquifer. Discontinuities (breaches) in the upper Claiborne confining unit (UCCU) allow for leakage into the Memphis aquifer, a sand-dominated aquifer that provides about 95% of the groundwater used in the Memphis area. This study created a multi-layered 3D groundwater model for Shelby County using the United States Geological Survey's MODFLOW-NWT program to evaluate water exchange for a simulation period from January 2005 to December 2016. Results indicate an overall leakage through the UCCU of 61 m
3 /min into the Memphis aquifer in Shelby County, accounting for 10% of its water budget inflow, with localized areas experiencing as much as 20% water exchange. As young water tends to stay in the upper part of the Memphis aquifer, water budget assessment for the upper 60 m of the Memphis aquifer revealed leakage representing 29% of the zone inflow, and as much as 53% in certain areas. More localized studies must be conducted to understand the location, characteristics, and orientation of the confining unit breaches, as well as the inter-aquifer water exchange. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
40. Percutaneous Endoscopic External Ring Hernioplasty Using Dundee Inguinal Canal Retractor.
- Author
-
Waldron, Brian, Frank, T., and Cuschieri, Alfred
- Published
- 1998
- Full Text
- View/download PDF
41. Application of Numerical Tools to Investigate a Leaky Aquitard beneath Urban Well Fields.
- Author
-
Jazaei, Farhad, Waldron, Brian, Schoefernacker, Scott, and Larsen, Daniel
- Subjects
AQUIFERS ,WATER quality ,GROUNDWATER remediation ,HYDROGEOLOGY ,WATER pollution - Abstract
Memphis aquifer is the primary drinking water source in Shelby County (Tennessee, USA), and it supplies industrial, commercial, and residential water. Memphis aquifer is separated from the Shallow aquifer by a clayey layer known as the Upper Claiborne confining unit (UCCU). All of the production wells in the Memphis area are screened in the Memphis aquifer, or even deeper in the Fort Pillow aquifer. Traditionally, it was assumed that the UCCU could fully protect the Memphis aquifer from the contaminated Shallow aquifer groundwater. However, recent studies show that at some locations, the UCCU is thin or absent, which possibly leads to the contribution of Shallow aquifer to the Memphis aquifer. Accurately locating the breaches demands expensive and difficult geological or geochemical investigations, especially within an urban area. Hence, a pre-field investigation to identify the locations where the presence of breaches is likely can significantly reduce the cost of field investigations and improve their results. In this study, to identify the locations where the presence of breaches in the UCCU is likely, we develop a reliable MODFLOW-based numerical model, and use three different analyses: (1) pilot-point calibration (PPC), (2) velocity and flow budget (VFB), and (3) particle tracking (PT), to post-process the developed groundwater model results. These pre-field numerical investigations provide relevant and defensible explanations for groundwater flow anomalies in an aquifer system for informed decision-making and future field investigations. In this study, we identify five specific zones within the broad study area which are reasonable candidates for the future field investigations. Finally, we test the results of each analysis against other evidence for breaches, to demonstrate that the results of the numerical analyses are reliable and supported by previous studies. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
42. HAVE YOUR SAY.
- Author
-
Waldron, Brian J.
- Published
- 2018
43. GIS-Based Gold Potential Mapping in the Muteh Deposit Area, Iran, with Respect to a New Mineralization Concept.
- Author
-
Javadnejad, Farid, Waldron, Brian A., and Alinia, Firooz
- Published
- 2013
- Full Text
- View/download PDF
44. Gastric cancer–related information on the Internet: incomplete, poorly accessible, and overly commercial
- Author
-
Killeen, Shane, Hennessey, Arthur, El Hassan, Yahear, Killeen, Kelvin, Clarke, Nick, Murray, Kevin, and Waldron, Brian
- Subjects
- *
STOMACH cancer , *INTERNET , *WEBSITES , *READABILITY (Literary style) , *RELIABILITY (Personality trait) , *WEB search engines - Abstract
Abstract: Background: Patients increasingly use the Internet for gastric cancer information. However, the quality of the information is questionable. We evaluated the accuracy, completeness, accessibility, reliability, and readability of gastric cancer websites. Methods: The Internet was searched for the terms “gastric cancer” or “stomach cancer” using general search engines. Websites were evaluated for completeness (CS) and accuracy (AS) using predefined quality appraisal instruments (QAIs), reliability using an integrity score (IS), readability using the Flesch-Kincaid (FK) grade level, and accessibility using automated accessibility appraisal tools. Site sponsor and the presence of quality labels were noted. Results: Fifty-one websites were evaluated. The mean CS was 100.3 (SD ±44.9), AS was 107.22 (SD ±47.9), IS was 15.3 (SD ±3.7), and the mean readability grade level was 10.4 (SD ±2.5). Only 5 websites had the minimum mandatory basic accessibility. Commercial sites and sites with quality labels had significantly more accessibility violations. Conclusions: Internet gastric cancer information is overtly commercial, generally incomplete, and poorly accessible. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
45. Reelfoot rift and its impact on Quaternary deformation in the central Mississippi River valley.
- Author
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Csontos, Ryan, Van Arsdale, Roy, Cox, Randel, and Waldron, Brian
- Subjects
- *
GEOSYNCLINES , *EARTHQUAKE zones , *SEISMOLOGY , *ALLUVIUM , *SEDIMENTS , *GEOMORPHOLOGY , *PHYSICAL geography - Abstract
Geophysical and drill-hole data within the Reelfoot rift of Arkansas, Tennessee, Missouri, and Kentucky, USA, were integrated to create a structure contour map and threedimensional computer model of the top of the Precambrian crystalline basement. The basement map and model clearly define the northeast- trending Cambrian Reelfoot rift, which is crosscut by southeast-trending basement faults. The Reelfoot rift consists of two major basins, separated by an intrarift uplift, that are further subdivided into eight subbasins bound by northeast- and southeast-striking rift faults. The rift is bound to the south by the White River fault zone and to the north by the Reelfoot normal fault. The modern Reelfoot thrust fault, responsible for most of the New Madrid seismic zone earthquakes, is interpreted as an inverted basement normal fault. Geologic interpretation of 5077 shallow borings in the central Mississippi River valley enabled the construction of a structure contour map of the Pliocene-Pleistocene unconformity (top of the Eocene-base of Mississippi River alluvium) that overlies most of the Reelfoot rift. This map reveals both river erosion and tectonic deformation. Deformation of the Pliocene-Pleistocene unconformity appears to be controlled by the northeast- and southeast-trending basement faults. The northeast-trending rift faults have undergone and continue to undergo Quaternary dextral transpression. This has resulted in displacement of two major rift blocks and formation of the Lake County uplift, Joiner ridge, and the southern half of Crowley's Ridge as compressional stepover zones that appear to have originated above basement fault intersections. The Lake County uplift has been tectonically active over the past ~2400 yr and corresponds with a major segment of the New Madrid seismic zone. The aseismic Joiner ridge and the southern portion of Crowley's Ridge may reflect earlier uplift, thus indicating Quaternary strain migration within the Reelfoot rift. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
46. Changes in aspects of social functioning depend upon prior changes in neurodisability in people with acquired brain injury undergoing post-acute neurorehabilitation.
- Author
-
Fortune DG, Walsh RS, Waldron B, McGrath C, Harte M, Casey S, and McClean B
- Abstract
Post-acute community-based rehabilitation is effective in reducing disability. However, while social participation and quality of life are valued as distal outcomes of neurorehabilitation, it is often not possible to observe improvements on these outcomes within the limited time-frames used in most investigations of rehabilitation. The aim of the current study was to examine differences in the sequence of attainments for people with acquired brain injury (ABI) undergoing longer term post-acute neurorehabilitation. Participants with ABI who were referred to comprehensive home and community-based neurorehabilitation were assessed at induction to service, at 6 months and again at 1.5 years while still in service on the Mayo-Portland Adaptability Index (MPAI-4), Community Integration Questionnaire, Hospital Anxiety and Depression Scale, and World Health Organisation Quality of Life measure. At 6 months post-induction to service, significant differences were evident in MPAI abilities, adjustment, and total neurodisability; and in anxiety and depression. By contrast, there was no significant effect at 6 months on more socially oriented features of experience namely quality of life (QoL), Community Integration and Participation. Eighteen month follow-up showed continuation of the significant positive effects with the addition of QoL-related to physical health, Psychological health, Social aspects of QoL and Participation at this later time point. Regression analyses demonstrated that change in QoL and Participation were dependent upon prior changes in aspects of neurodisability. Age, severity or type of brain injury did not significantly affect outcome. Results suggest that different constructs may respond to neurorehabilitation at different time points in a dose effect manner, and that change in social aspects of experience may be dependent upon the specific nature of prior neurorehabilitation attainments.
- Published
- 2015
- Full Text
- View/download PDF
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