The manipulation of water resources is a common human solution to water-related problems. Of particular interest because of impacts on both source and destination is the anthropogenic movement of water from one basin to another, or inter-basin transfers (IBTs). In the United States, IBTs occur widely in both wet and dry regions, but IBT data are not collated and served in a coordinated way.
View Article and Find Full Text PDFThe worsening opioid epidemic ignites infectious disease development and transmission as opioids abused by insufflation and/or injection establish a pathway for infection to the user and propagate vulnerability to diseases. The phenomenon of the synergistic collision of epidemics intensifying the load of disease constitutes a syndemic. Merrill Signer (1994) voiced the term "syndemic" to characterize the complex nexus of politics, economics, psychosocial/environmental factors, and health disparities resulting in the inner-city AIDS crisis of the 1990s.
View Article and Find Full Text PDFIn the wake of epidemic of opioid overdoses in the United States, patients who are receiving treatment for chronic pain with opioid have come under increasing scrutiny. The Centers for Disease Control and Prevention issued a guideline for managing chronic pain in 2016, which makes recommendations for opioids based on current evidence. This review will highlight key components of the guideline including differentiating addiction from dependence to assist nurses to better inform patient care in managing chronic pain.
View Article and Find Full Text PDFLittle is known about the experiences of patients with severe comorbidity discharged from Intensive Care Units (ICUs). This project aimed to determine the effects of an ICU stay for patients with severe comorbidity by comparing 1) quality of life (QOL), 2) the symptom profile of hospital survivors and 3) health service use after hospital discharge for patients admitted to ICU with and without severe comorbidity. A case-control study was used.
View Article and Find Full Text PDFIn this study, plasma-polymerized films are evaluated as enrichment membranes deposited at the surface of mid-infrared transparent waveguides for liquid-phase chemical sensing utilizing evanescent field absorption spectroscopy. Fluorocarbon films were deposited onto zinc selenide (ZnSe) waveguides from plasma-polymerized pentafluoroethane (CF(3)CHF(2)) vapor. Excellent optical transmission of ZnSe waveguides after plasma deposition confirms compatibility of the infrared transparent substrate with this low-temperature, solvent-free film deposition process.
View Article and Find Full Text PDFIn this work, the potential for natural attenuation (NA) of Cr(VI) is evaluated for sub-wetland ground water at a chromium-contaminated site in Connecticut, incorporating the experimental findings of previous work at the site. Experimental data is assessed through long-term attenuation capacity calculations and modeling, which incorporates statistical uncertainty of parametric values. The NA evaluation yielded the following results: (1) Significant increases in Cr(VI) concentration and extremely long chromium source dissolution timeframes are required to exceed the attenuation capacity of the sub-wetland region soils studied in this work; and (2) Based on the 1-D transport modeling and incorporating input parameter uncertainty, there is an approximately 92% and 98% probability that the applicable regulatory criteria will not be exceeded at Point C, near a river which serves as the receptor, for the cases of (1) sorption of Cr(VI) only and (2) pseudo first order disappearance of Cr(VI) from the aqueous phase only, respectively.
View Article and Find Full Text PDFA combined experimental and spectral ray tracing approach for identifying and evaluating evanescent field interactions with discrete surface deposits along a horizontal attenuated total reflection (HATR) element is presented. By experimentally depositing poly(styrene-co-butadiene) (PSCB) residues at fixed intervals along the measurement surface of a HATR crystal, distinct regions of evanescent field interaction with the surface deposits along the multi-reflection waveguide are visualized via infrared absorption features of PSCB. The infrared-attenuated total reflection (IR-ATR) measurements were confirmed by spectral ray tracing analysis simulating transmission-absorption spectra after modeling the polymeric surface deposits as thin-film IR absorbing cylinders.
View Article and Find Full Text PDFAn arsenic contaminated lake sediment near a landfill in Maine was used to characterize the geochemistry of arsenic and assess the influence of environmental conditions on its mobility. A kinetic model was developed to simulate the leaching ability of arsenic in lake sediments under different environmental conditions. The HM1D chemical transport model was used to model the column experiments and determine the rates of arsenic mobility from the sediment.
View Article and Find Full Text PDFField and laboratory studies were conducted to elucidate the design factors and mechanisms of arsenic removal from contaminated ground water using zero-valent iron. Large scale, field pilot experiments demonstrated for more than 8 months that iron filing filters can efficiently remove arsenite from aqueous solutions to levels less than 10 micro g/L. The maximum arsenic accumulation measured was 4.
View Article and Find Full Text PDFThe kinetics, reaction pathways and product distribution of oxidation of tetrachloroethylene (PCE) by potassium permanganate (KMnO4) were studied in phosphate-buffered solutions under constant pH, isothermal, completely mixed and zero headspace conditions. Experimental results indicate that the reaction is first-order with respect to both PCE and KMnO4 and has an activation energy of 9.3+/-0.
View Article and Find Full Text PDFFenton's reagent is the result of reaction between hydrogen peroxide (H(2)O(2)) and ferrous iron (Fe(2+)), producing the hydroxyl radical (-*OH). The hydroxyl radical is a strong oxidant capable of oxidizing various organic compounds. The mechanism of oxidizing trichloroethylene (TCE) in groundwater and soil slurries with Fenton's reagent and the feasibility of injecting Fenton's reagent into a sandy aquifer were examined with bench-scale soil column and batch experiment studies.
View Article and Find Full Text PDFThe kinetics of oxidation of perchloroethylene (PCE), trichloroethylene (TCE), three isomers of dichloroethylene (DCE) and vinyl chloride (VC) by potassium permanganate (KMnO(4)) were studied in phosphate-buffered solutions of pH 7 and ionic strength approximately 0.05 M and under isothermal, completely mixed and zero headspace conditions. Experimental results have shown that the reaction appears to be second order overall and first order individually with respect to both KMnO(4) and all chlorinated ethenes (CEs), except VC.
View Article and Find Full Text PDFComplete serial sections demonstrated that ten species of Antarctic teleost fishes representing two families had aglomerular kidneys. The aglomerular nephron of such kidneys consists of two distinct regions: (1) a highly contorted principal segment and (2) a system of collecting tubules and ducts. Throughout the principal segment the cells are characterized by densely packed microbilli and a single cilium projecting into the lumen.
View Article and Find Full Text PDFUrine formation in antarctic bony fish does not involve glomerular filtration. Evidence for aglomerularism came from both direct observation of kidney serial sections by light microscopy and the low concentrations of inulin labeled with carbon-14 that were excreted into the urine when this renal clearance tracer was injected into the bloodstream via a cannula implanted in the caudal vein. Aglomerularism most likely prevents urinary loss of glycoproteins with biological antifreeze properties.
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