122 research outputs found

    Effect of Petroleum Hydrocarbons on Microbial Populations in an Arctic Lake

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    A sea-curtain enclosed section of a lake 240 km south of Prudhoe Bay, Alaska was exposed to Prudhoe crude oil in July 1976. One year following exposure to the oil, no significant differences were detected between the waters or sediments of the oiled versus control area in rates of turnover of glucose. Total numbers of bacteria were slightly higher in oiled than in control waters. There were no differences in numbers of sediment bacteria. Rates of uptake of hexadecane and napthalene by sediment microbes were not linear with time. Hexadecane was taken up sooner and faster than was napthalene. In 0 some incubations, significantly (88 - 95% probability level) greater rates of hydrocarbon uptake were measured for oiled than for control sediments. Only incorporated, not mineralized, hydrocarbons were measured due to methodological problems. Several methods of using 14C-labelled hydrocarbons in a field situation are presented

    The Role of the Pediatric Nurse Practitioner in the Comprehensive Management of Pediatric Oncology Patients in the Inpatient Setting

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    The role of the pediatric nurse practitioner (PNP) in the comprehensive management of pediatric oncology patients in the inpatient setting was examined at a large tertiary teaching hospital. This article shows role responsibilities including new diagnosis teaching, procedures, routine chemotherapy, patients' comprehensive medical management, coordination of nursing care across settings, phone triage, and professional development. A PNP's typical day is highlighted to illustrate the innovative merging of traditional ambulatory care roles with that of the PNP as a comprehensive manager of pediatric oncology patients in the inpatient setting. This role provides a more seamless care experience and provides critical links in the delivery of health care to pediatric oncology patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68349/2/10.1177_104345429901600202.pd

    Antimicrobial Resources for Disinfection of Potable Water Systems for Future Spacecraft

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    As human exploration adventures beyond low earth orbit, life support systems will require more innovation and research to become self-sustaining and durable. One major concern about future space travel is the ability to store and decontaminate water for consumption and hygiene. This project explores materials and technologies for possible use in future water systems without requiring point-of-use (POU) filtering or chemical additives such as iodine or silver that require multiple doses to remain effective. This experimentation tested the efficacy of a variety of antimicrobial materials against biofilm formation in a high shear CDC Biofilm Reactor (CBR) and some materials in a low shear Drip Flow Reactor (DFR) which(also utilizes ultra violet light emitting diodes (UVLEDs) as an antimicrobial resource. Most materials were tested in the CBR using the ASTM E 2562-07 1method involving the Pseudomonas aeruginosa and coupon samples that vary in their antimicrobial coatings and surface layer topographies. In a controlled environmental chamber (CEC), the CBR underwent a batch phase, continuous flow phase (CFP), and a harvest before analysis. The DFR portion of this experimentation was performed in order to assess the antimicrobial capabilities of ultraviolet-A LEDs (UV-A) in potable water systems. The ASTM E 2647-08 was modified in order to incorporate UV-A LEDs and to operate as a closed, re-circulating system. The modified DFR apparatus that was utilized contains 4 separate channels each of which contain 2 UV-A LEDs (1 chamber is masked off to serve as a control) and each channel is equipped with its own reservoir and peristaltic pump head. The 10 DFR runs discussed in this report include 4 initial experimental runs that contained blank microscope slides to test the UVA LEDs alone, 2 that incorporated solid silver coupons, 2 that utilized titanium dioxide (Ti02) coupons as a photocatalyst, and 2 runs that utilized silver coated acrylic slides. Both the CBR and DFR experiments were analyzed for microbial content via heterotrophic plate counts (HPC) and acridine orange direct counts (AODC). Ofthe materials used in the CBR, only two materials performed as anti~icrobials under high shear conditions (a reduction of 5 or more logs) showing a>7 log reduction in viable microbes

    Effects of oil on a tundra pond. Final report

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    A three year study of two spills in tundra ponds at Barrow showed that oil has a highly specific impact on the benthos. Instead of a toxic effect on the entire community, as occurred with the crustacean zooplankton, certain insect species inhabiting the vegetated margins of the ponds were eliminated. Physical entrapment by the floating oil slick or the film coating stems of emergent sedges and grasses appeared to cause this mortality, and species specific behaviors may be responsible for the observed selectivity. Recovery of affected populations may take years due to the long life cycles of arctic insects, and the poor dispersal capabilities of many arctic species. Large scale spills covering many contiguous lakes and ponds could have especially long lasting impacts
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