67 research outputs found
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Development and Field Evaluation of an Aquifer Stratification Testing System
An aquifer stratification testing system was designed, constructed, and tested. The system was designed to characterize vertical profiles of both quantity and quality of water produced from actively pumping groundwater wells. During testing, all systems functioned properly and either met or exceeded anticipated performance requirements. The system was first tested in an irrigation well completed in the Edwards aquifer and owned by the Onion Creek Club located in Manchaca, Texas, just south of Austin. The purpose of the exercise was to assess test systems performance and to develop and refine testing procedures. Dye-tracer injection tests were performed at five depths from 325 to 405 ft, and a velocity/discharge profile was generated for that interval. The profile was consistent with the karst nature of the Edwards aquifer. Water sampling procedures were tested and evaluated, but no samples were analyzed.
Further testing was performed in two public water supply wells completed in the Ogallala Formation of the High Plains aquifer and belonging to the City of Wolfforth, Texas, to investigate arsenic and fluoride concentration distributions, which both exceed maximum contaminant level (MCL) standards for arsenic (10 μg/L) and fluoride (4 mg/L) in produced water. The results indicated vertical trends in both arsenic and fluoride aquifer concentration profiles, although concentrations at all depths exceeded MCL standards for both arsenic and fluoride. Despite distinctly different water discharge profiles between wells, a consistent inverse depth relationship between arsenic and fluoride concentrations was identified in both wells. Aquifer arsenic concentrations generally decreased, and aquifer fluoride concentrations generally increased with increasing depth. Aquifer arsenic concentrations ranged from 11.4 to 14.1 μg/L in Well 8 and from 16.0 to 22.2 μg/L in Well 5. Aquifer fluoride concentrations ranged from 5.53 to 7.98 mg/L in Well 8 and from 4.28 to 5.87 mg/L in Well 5.
Future system and procedural modifications should focus on improving and enhancing the flexibility and data acquisition capabilities of the system. Future field testing programs should be performed to develop a water quality stratification database to enhance general understanding of groundwater quality and flow processes and provide insight on potential contamination sources.Bureau of Economic Geolog
Small-Scale Hydroelectric Power for Remote Communities
The Pico-Hydro Energy Project (PHEP) focuses on providing affordable electric power for off-grid communities in developing countries. The work that PHEP is doing involves the design, optimization, and experimental testing of small hydroelectric generators provided by our project partner Engineering Ministries International.https://mosaic.messiah.edu/engr2020/1000/thumbnail.jp
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Ground Water Surface Water Interactions in Texas
Groundwater-surface water interactions need to be evaluated to optimize water management in Texas. This study provides an overview of the impacts of groundwater-surface water (gw-sw) interactions on water quality and water quantity using available data. A literature review was conducted to assess the status of knowledge of gw-sw interactions. A total of 300 references were compiled. References were subdivided into those related to water quantity issues, water quality including point and nonpoint sources of contamination, and methods such as seepage and temperature approaches and modeling analyses. Additional topics covered by the reference list include impacts of climate variability and land use/land cover changes on gw-sw interactions and ecological issues. A compilation of data and information sources for assessing gw-sw interactions in Texas is also provided. This section includes web links to online report catalogs and databases and a listing of offline reports and catalogs provided by state and federal agencies.Bureau of Economic Geolog
A 4500-year time series of Pacific cod (Gadus macrocephalus) size and abundance: archaeology, oceanic regime shifts, and sustainable fisheries
A 4500-year archaeological record of Pacific cod (Gadus macrocephalus) bones from Sanak Island, Alaska, was used to assess the sustainability of the modern fishery and the effects of this fishery on the size of fish caught. Allometric reconstructions of Pacific cod length for eight
prehistoric time periods indicated that the current size of the nearshore, commercially fished Pacific cod stocks
is statistically unchanged from that of fish caught during 4500 years of subsistence harvesting. This finding
indicates that the current Pacific cod fishery that uses selective harvesting technolog ies is a sustainable
commercial fishery. Variation in relative Pacific cod abundances provides further insights into the response of
this species to punctuated changes in ocean climate (regime shifts) and indicates that Pacific cod stocks can recover from major environmental perturbations. Such palaeofisheries
data can extend the short time-series of fisheries data (<50 yr) that form the basis for fisheries management in
the Gulf of Alaska and place current trends within the context of centennial- or millennial-scale patterns
Epidemiology of melanoma in rural southern Queensland
Objective: The objective of this study is to define the epidemiology of melanoma in rural communities in southern Queensland.
Design: The design used was a 6‐year clinical record audit of melanoma cases identified by billing records and electronic clinical records, confirmed and typed with
histology.
Setting and Participants: This study was based on seven agricultural communities on the Darling Downs with patients presenting to local primary care clinics.
Main outcome measures: Outcomes measured were confirmed type, depth and anatomic distribution of melanoma identified at these practices during the study period.
Results: The results from 317 cases of melanoma found anatomic distribution was significantly different (χ2 = 9.6, P < 0.05) to that reported previously from the
Queensland Cancer Registry. A high proportion (87%) of melanoma diagnosed by these general practitioners were 1 mm or less when treated.
Conclusions: Conclusions drawn from these findings are that melanoma risk is not so much lesser in rural, inland communities compared with coastal and metropolitan
regions, but different. Differences may relate to comprehensive data capture available in rural community studies and to different sun exposure and protection behaviours. The higher proportion of melanoma identified at early stages suggests rural primary care is an effective method of secondary prevention
Axial and Radial Forces of Cross-Bridges Depend on Lattice Spacing
Nearly all mechanochemical models of the cross-bridge treat myosin as a simple linear spring arranged parallel to the contractile filaments. These single-spring models cannot account for the radial force that muscle generates (orthogonal to the long axis of the myofilaments) or the effects of changes in filament lattice spacing. We describe a more complex myosin cross-bridge model that uses multiple springs to replicate myosin's force-generating power stroke and account for the effects of lattice spacing and radial force. The four springs which comprise this model (the 4sXB) correspond to the mechanically relevant portions of myosin's structure. As occurs in vivo, the 4sXB's state-transition kinetics and force-production dynamics vary with lattice spacing. Additionally, we describe a simpler two-spring cross-bridge (2sXB) model which produces results similar to those of the 4sXB model. Unlike the 4sXB model, the 2sXB model requires no iterative techniques, making it more computationally efficient. The rate at which both multi-spring cross-bridges bind and generate force decreases as lattice spacing grows. The axial force generated by each cross-bridge as it undergoes a power stroke increases as lattice spacing grows. The radial force that a cross-bridge produces as it undergoes a power stroke varies from expansive to compressive as lattice spacing increases. Importantly, these results mirror those for intact, contracting muscle force production
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Food Consumption and its Impact on Cardiovascular Disease: Importance of Solutions Focused on the Globalized Food System A Report From the Workshop Convened by the World Heart Federation
Major scholars in the field, based on a 3-day consensus, created an in-depth review of current knowledge on the role of diet in CVD, the changing global food system and global dietary patterns, and potential policy solutions. Evidence from different countries, age/race/ethnicity/socioeconomic groups suggest the health effects studies of foods, macronutrients, and dietary patterns on CVD appear to be far more consistent though regional knowledge gaps are highlighted. There are large gaps in knowledge about the association of macronutrients to CVD in low- and middle-income countries (LMIC), particularly linked with dietary patterns are reviewed. Our understanding of foods and macronutrients in relationship to CVD is broadly clear; however major gaps exist both in dietary pattern research and ways to change diets and food systems. Based on the current evidence, the traditional Mediterranean-type diet, including plant foods/emphasizing plant protein sources, provides a well-tested healthy dietary pattern to reduce CV
Kepler K2 Campaign 9: II. First space-based discovery of an exoplanet using microlensing
We report on the discovery of a bound exoplanetary microlensing event from a
blind search of data gathered from Campaign 9 of the Kepler K2 mission (K2C9).
K2-2016-BLG-0005Lb is a densely sampled, binary caustic-crossing microlensing
event with caustic entry and exit points that are resolved in the K2C9 data,
enabling the lens-source relative proper motion to be measured. We have fitted
a binary microlens model to the K2 dataset, and to simultaneous observations
from the Optical Gravitational Lensing Experiment (OGLE-IV),
Canada-France-Hawaii Telescope (CFHT), Microlensing Observations in
Astrophysics (MOA-2), the Korean Microlensing Telescope Network (KMTNet), and
the United Kingdom InfraRed Telescope (UKIRT). Whilst the ground-based data
only sparsely sample the binary caustic, they provide a clear detection of
parallax that allows us to break completely the microlensing
mass-position-velocity degeneracy and measure the planet's mass directly. We
find a host mass of and a planetary mass of . The system lies at a distance of kpc from
Earth towards the Galactic bulge. The projected physical separation of the
planet from its host is found to be au which, for circular
orbits, corresponds to au and period yr, making K2-2016-BLG-0005Lb a close Jupiter analogue. Though
previous exoplanet microlensing events have included space-based data, this
event is the first bound microlensing exoplanet to be discovered from
space-based data. Even through a space telescope not designed for microlensing
studies, this result highlights the advantages for exoplanet microlensing
discovery that come from continuous, high-cadence temporal sampling that is
possible from space. (Abridged).Comment: 17 pages. Submitted to MNRA
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<i>Kepler K2</i> Campaign 9: II. First space-based discovery of an exoplanet using microlensing
We present K2-2016-BLG-0005Lb, a densely sampled, planetary binary caustic-crossing microlensing event found from a blind search of data gathered from Campaign 9 of the Kepler K2 mission (K2C9). K2-2016-BLG-0005Lb is the first bound microlensing exoplanet discovered from space-based data. The event has caustic entry and exit points that are resolved in the K2C9 data, enabling the lens–source relative proper motion to be measured. We have fitted a binary microlens model to the Kepler data, and to simultaneous observations from multiple ground-based surveys. Whilst the ground-based data only sparsely sample the binary caustic, they provide a clear detection of parallax that allows us to break completely the microlensing mass–position–velocity degeneracy and measure the planet’s mass directly. We find a host mass of 0.58 ± 0.04M⊙ and a planetary mass of 1.1 ± 0.1MJ. The system lies at a distance of 5.2 ± 0.2 kpc from Earth towards the Galactic bulge, more than twice the distance of the previous most distant planet found by Kepler. The sky-projected separation of the planet from its host is found to be 4.2 ± 0.3 au which, for circular orbits, deprojects to a host separation au and orbital period yr. This makes K2-2016-BLG-0005MLb a close Jupiter analogue orbiting a low-mass host star. According to current planet formation models, this system is very close to the host mass threshold below which Jupiters are not expected to form. Upcoming space-based exoplanet microlensing surveys by NASA’s Nancy Grace Roman Space Telescope and, possibly, ESA’s Euclid mission, will provide demanding tests of current planet formation models
Enhancing nursing education with remote access laboratories
Given the vast coverage area and dispersed population centres in which nursing professionals practice in Australia, Remote Access Laboratory (RAL) based learning activities would seem to be an ideal match. However while they are commonplace in engineering faculties; in other disciplines such activities are not widely used. This may well be due to the intricacies of these practicals not being as straightforward and readily reproducible as typical physics or science experiments.
In our chosen case, the safe practice of intravenous pump driver operations and related clinical reasoning skills are important components for the training of both registered nurses and nursing students. The aim of this research project is to develop and trial remote access technologies that enable nursing students to test their knowledge, skills, and clinical reasoning with intravenous infusion pump drivers. This has been possible by extending the concept of RAL from a physical and tangible experiment, to more conceptual experimentation in any form conducted remotely. In such a context clinical reasoning becomes possible.
This paper discusses a prototype system that has been built with collaborative input from the Faculty of Engineering and Surveying and the Department of Nursing and Midwifery. An initial evaluation with a group of nursing students has been completed to assess if such activities can assist with the training of student nurses. Previous work has identified the need to scaffold learning activities that rely on RAL technology; the key conclusion in this paper is that in the context of nursing this has to be taken a step further. RAL activities here require contextualisation to become an effective learning tool
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