948 research outputs found

    Nutrient Sources in the Clark Fork River Basin

    Get PDF
    Under Section 525 of the 1987 amendments to the federal Clean Water Act, Montana initiated an intensive monitoring program to identify and rank the major point and nonpoint sources of nutrients to the Clark Fork River. A 51 station monitoring network was established, including 19 stations on the Clark Fork River, 22 stations on tributary streams, and 10 municipal and industrial wastewater discharges to the river. In the first year of monitoring, samples were collected 15 times and analyzed for total and soluble forms of phosphorus and nitrogen. Several small tributaries to the upper Clark Fork (Gold, Flint, Lost, Racetrack, and Dempsey creeks and the Mill-Willow Bypass) and all 10 wastewater discharges exhibited elevated nutrient concentrations. The Missoula, Butte, and Deer Lodge municipal wastewater discharges were responsible for the largest nutrient concentrations in the Clark Fork. Inflows from good quality tributaries such as Rock Creek and the Blackfoot, Little Blackfoot, Bitterroot, and Flathead rivers were important in diluting nutrient concentrations in the Clark Fork. Overall, soluble phosphorus loading to the Clark Fork originated about equally from tributary inflows and wastewater discharges. About two-thirds of the soluble nitrogen loading came from tributaries, with effluents contributing the remaining third. During the summer low flow period, an even greater share of the soluble nutrient loading came from effluents. Tributary sources of soluble nutrient loading were dominated by the Flathead, Bitterroot, and Blackfoot rivers. Gold and Flint creeks ranked fourth in importance as tributary sources of soluble phosphorus and nitrogen, respectively. The Missoula, Butte, and Deer Lodge municipal wastewater treatment plants and the Stone Container Corporation kraft mill discharged most of the soluble nutrient loading from effluents. However, the Warm Springs treatment ponds on Silver Bow Creek removed most of the Butte nutrient load prior to reaching the Clark Fork River

    Generalized analysis of quasi-steady-state and transient decay open circuit voltage measurements

    No full text
    The current–voltage characteristics of solar cells and photodiodes can be determined by measuring the open-circuit voltage as a function of a slowly varying light intensity. This article presents a detailed theoretical analysis and interpretation of such quasi-steady-state Vocmeasurements(QssVoc). The ability of this analysis to accurately obtain the true steady-state device characteristics even in the case of high lifetime, high resistivitysilicon devices is demonstrated experimentally. The QssVoc technique can be used to determine the minority carrier lifetime, and the new generalized analysis is required to do this accurately. An important outcome is that solar cell and diode device characteristics can be obtained from measurements of either the photoconductance or the open-circuit voltage, even using transient techniques.This work has been funded by the Australian Research Council. The authors also thank S. Glunz and S. Rein from the Fraunhofer Institute of Solar Energy Systems, for the use of the solar cell used in Fig. 5

    Frequency of cannabis and illicit opioid use among people who use drugs and report chronic pain: A longitudinal analysis.

    Get PDF
    BACKGROUND:Ecological research suggests that increased access to cannabis may facilitate reductions in opioid use and harms, and medical cannabis patients describe the substitution of opioids with cannabis for pain management. However, there is a lack of research using individual-level data to explore this question. We aimed to investigate the longitudinal association between frequency of cannabis use and illicit opioid use among people who use drugs (PWUD) experiencing chronic pain. METHODS AND FINDINGS:This study included data from people in 2 prospective cohorts of PWUD in Vancouver, Canada, who reported major or persistent pain from June 1, 2014, to December 1, 2017 (n = 1,152). We used descriptive statistics to examine reasons for cannabis use and a multivariable generalized linear mixed-effects model to estimate the relationship between daily (once or more per day) cannabis use and daily illicit opioid use. There were 424 (36.8%) women in the study, and the median age at baseline was 49.3 years (IQR 42.3-54.9). In total, 455 (40%) reported daily illicit opioid use, and 410 (36%) reported daily cannabis use during at least one 6-month follow-up period. The most commonly reported therapeutic reasons for cannabis use were pain (36%), sleep (35%), stress (31%), and nausea (30%). After adjusting for demographic characteristics, substance use, and health-related factors, daily cannabis use was associated with significantly lower odds of daily illicit opioid use (adjusted odds ratio 0.50, 95% CI 0.34-0.74, p < 0.001). Limitations of the study included self-reported measures of substance use and chronic pain, and a lack of data for cannabis preparations, dosages, and modes of administration. CONCLUSIONS:We observed an independent negative association between frequent cannabis use and frequent illicit opioid use among PWUD with chronic pain. These findings provide longitudinal observational evidence that cannabis may serve as an adjunct to or substitute for illicit opioid use among PWUD with chronic pain

    Profiling Indiana\u27s 4-H Horse and Pony Leaders

    Get PDF
    This article profiles Indiana\u27s nearly 600 4-H horse and pony leaders, describes their motives for becoming a leader, and documents the understanding these leaders have of running a 4-H club, teaching various aspects of the horse and pony project, and training hippology, horse bowl, and horse judging teams. The majority (\u3e70%) of Indiana\u27s 4-H horse and pony leaders are white, married women between the ages of 31 and 50. Eighty-eight percent volunteer as leaders because they enjoy working with youth. Over half (54%) of the leaders would like to receive additional training on how to conduct showmanship and horsemanship clinics

    Pursuing the Ephemeral, Painting the Enduring: Alzheimer\u27s and the Artwork of William Utermohlen

    Get PDF
    This book is published in conjunction with the exhibition Pursuing the Ephemeral, Painting the Enduring: Alzheimer’s and the Artwork of William Utermohlen, Exhibition and Scholarly Reflections presented at Illinois Wesleyan University Wakeley Gallery November 6 to December 11, 2015. The exhibition and catalogue are partially funded by a grant from the Andrew W. Mellon Foundation. William Utermohlen’s work is represented by Chris Boïcos Fine Arts, Paris and Jennifer Norback Fine Arts, Chicago.https://digitalcommons.iwu.edu/utermohlen/1000/thumbnail.jp

    An inexpensive device to treat postpartum hemorrhage: a preliminary proof of concept study of health provider opinion and training in Nepal

    Get PDF
    BACKGROUND: Obstetric hemorrhage remains the leading cause of maternal mortality in resource limited areas. An inexpensive pneumatic anti-shock garment was devised of bicycle tubes and tailored cloth which can be prepared from local materials in resource-limited settings. The main purposes of this study were: 1) to determine acceptability of the device by nurses and midwives and obtain suggestions for making the device more suitable for use in their particular work environments, 2) to determine whether a three hour training course provided adequate instruction in the use of this device for the application of circumferential abdominal pelvic pressure, and 3) determine production capability and cost in a resource-limited country. METHODS: Fifty-eight nurse and midwife participants took part in three sessions over eight months in Nepal. Correct device placement was assessed on non-pregnant participants using ultrasound measurement of distal aortic flow before and after device inflation, and analyzed using confidence intervals. Participants were surveyed to determine acceptability of the device, obtain suggestions for improvement, and to collect data on clinical use. RESULTS: Device placement achieved flow decreases with a mean of 39% (95% CI 25%-53%, p < 0.001) in the first session, 28% (95% CI 21%-33%, P < 0.001) after four months and 29% (95% CI 24%-34%, p < 0.001) at 8 months. All nurses and midwives thought the device would be acceptable for use in obstetric hemorrhage and that they could make, clean, and apply it. They quickly learned to apply the device, remembered how to apply it, and were willing and able to use the device clinically. Ten providers used the device, each on one patient, to treat obstetric hemorrhage after routine measures had failed; bleeding stopped promptly in all ten, two of whom were transported to the hospital. Production of devices in Kathmandu using local tailors and supplies cost approximately $40 per device, in a limited production setting. CONCLUSIONS: Preliminary data suggest that an inexpensive, easily-made device is potentially an appropriate addition to current obstetric hemorrhage treatment in resource-limited areas and that further study is warranted

    The Impact of Carbohydrate and Protein Level and Sources on Swine Manure Foaming Properties

    Get PDF
    This study explored the impact of swine diet on the composition, methane production potential, and foaming properties of manure. Samples of swine manure were collected from controlled feeding trials with diets varying in protein and carbohydrate levels and sources. Protein sources consisted of corn with amino acids, corn-soybean meal with amino acids, corn-soybean meal, corn-canola meal, corn-corn gluten meal, and corn-poultry meal. Carbohydrate sources consisted of corn-soybean meal, barley, beet pulp, distillers dried grains with solubles (DDGS), soy hulls, and wheat bran. Manure samples were tested for a number of physical and biochemical parameters, including total solids, volatile solids, viscosity, density, methane production rate, biochemical methane potential, foaming capacity, and foam stability. Statistical analyses were performed to evaluate whether different carbohydrate and/or protein ingredients affected these physico-chemical properties or the samples’ ability to produce methane gas. After conducting these trials, another feeding trial was performed to evaluate if the addition of Narasin into rations (corn-soybean and DDGS) could reduce the methane production rate or potential of the manure. These samples were also tested for the physical and biochemical parameters mentioned previously. Finally, an additional manure foaming study was conducted involving the addition of specific carbohydrates ground to different particle sizes and corn oil to observe the effects that the additives had on foaming capacity and stability

    Three-Phase Foam Analysis and the Development of a Lab-Scale Foaming Capacity and Stability Test for Swine Manures

    Get PDF
    Foam accumulation on the manure slurry at deep pit swine facilities has been linked to flash fire incidents, making it a serious safety concern for pork producers. In order to investigate this phenomenon, samples of swine manure were collected from over 50 swine production facilities in Iowa with varying levels of foam accumulation over a seven month period. These samples were tested for a number of physical and chemical parameters including temperature, pH, total solids, volatile solids, volatile fatty acid concentration, biochemical methane potential, and methane production rate. After establishing these parameters, a foaming capacity and stability test was performed where samples were placed in clear PVC tubes with air diffusers at the bottom to simulate biogas production. The amount of foam produced at a set aeration rate was recorded as a measure of foaming capacity, and foam stability was assessed by measuring the height of foam remaining at certain time intervals after aeration had ceased. The results of this test indicated that samples collected from foaming barns showed a greater capacity to produce and stabilize foam. In addition, statistical analysis indicated that manures with foam produced methane at significantly greater rates than non-foaming manures (0.154 ± 0.010 and 0.052 ± 0.003 L CH4./L slurry*day respectively, average standard error), and consequently had significantly greater fluxes of methane moving through the manure volume. On the other hand, the biochemical methane production assay suggested that manure from foaming pits had less potential to generate methane (112 ± 9 mL CH4/g VS) than non-foaming pits (129 ± 9 mL CH4/g VS), and the VFA analysis showed significantly lower concentrations in foaming pits (4472, 3486, and 1439 μg/g for the surface level and descending depths of the pit, respectively) as compared to non-foaming pits (9385,8931, and 6938 μg/g for the same sample depths). When taken together, these assays suggest enhanced anaerobic digestion efficiency from foaming barns, as well as the possible accumulation of a surfactant at the manure-air interface of foaming deep pits. Overall, this work supports a three-phase system conceptualization of foam production in swine manure deep pits, and that the control of one or more of these phases will be required for mitigation

    65-micron thin monocrystalline silicon solar cell technology allowing 12-fold reduction in silicon usage

    Get PDF
    Thin (<70 micron) single crystal silicon solar cells have been manufactured through the use of a novel process involving selective etching. Narrow grooves are micromachined through the wafer using a standard micromachining technique with cells manufactured on the resulting silicon strips. These bifacial cells have a much greater surface area than the original wafer, leading to dramatic decreases in processing effort and silicon usage. Individual cells fabricated using the new process have displayed efficiencies up to 17.5% while a 560cm2 prototype module has displayed an efficiency of 12.3%. The size, thickness and bifacial nature of the cells offer the opportunity for a wide variety of module architectures and applications
    • …
    corecore