ABSTRACT
Methane (CH4) is the second most important greenhouse gas after carbon dioxide (CO2) and is inter alia produced in natural freshwater ecosystems. Given the rise in CH4 emissions from natural sources, researchers are investigating environmental factors and climate change feedbacks to explain this increment. Despite being omnipresent in freshwaters, knowledge on the influence of chemical stressors of anthropogenic origin (e.g., antibiotics) on methanogenesis is lacking. To address this knowledge gap, we incubated freshwater sediment under anaerobic conditions with a mixture of five antibiotics at four levels (from 0 to 5000 µg/L) for 42 days. Weekly measurements of CH4 and CO2 in the headspace, as well as their compound-specific δ13C, showed that the CH4 production rate was increased by up to 94% at 5000 µg/L and up to 29% at field-relevant concentrations (i.e., 50 µg/L). Metabarcoding of the archaeal and eubacterial 16S rRNA gene showed that effects of antibiotics on bacterial community level (i.e., species composition) may partially explain the observed differences in CH4 production rates. Despite the complications of transferring experimental CH4 production rates to realistic field conditions, the study indicated that chemical stressors contribute to the emissions of greenhouse gases by affecting the methanogenesis in freshwaters.
ABSTRACT
Meeting the many needs of a young adolescent on a busy Saturday can be quite a challenge. This article shows how a nurse practitioner drew on Watson's theory of caring as the basis of her interaction with an 11-year-old boy and his mother and relied on her ability to be flexible and creative in the process. The positive outcomes of this visit were evident in the client's and mother's change of affect and their commitment to take positive action. the nurse practitioner experienced renewal of spirit and a sense of gratitude for the effective role she played in this interaction.
Subject(s)
Holistic Health , Holistic Nursing , Nurse-Patient Relations , Nursing Process , Obesity/nursing , Adult , Anecdotes as Topic , Child , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Mother-Child Relations , Obesity/psychologyABSTRACT
Sterility testing on autoclaved surgical trays provides scientific information on the duration for which an item can be safely stored. Previous studies were performed by sampling at various time-points after storage and did not take into account potential injuries (moving, lifting etc.) to these trays as they occur in a clinical setting. A standardized protocol was developed by an expert panel based on events which were frequently observed in the Central Sterilization area. We tested 600 samples in 100 surgical trays that were moved and transported according to the standardized protocol. Moved surgical trays were contaminated in 8.3% of tests, a figure much higher than that reported by previous studies. These data suggest that current standards for sterility testing of autoclaved surgical trays can be improved by the addition of event-related testing.
Subject(s)
Central Supply, Hospital/standards , Equipment Contamination/prevention & control , Sterilization/standards , Surgical Instruments/standards , Environmental Microbiology , Environmental Monitoring , Evaluation Studies as Topic , Hospitals, University/standards , Humans , Iowa , Quality ControlABSTRACT
The influence of environmental factors on the tolerated feeding volumes as well as on the frequency of breathing were studied in 32 infants. During intensive neonatal care the tolerated feeding volumes were decreased and also the frequencies of breathing were influenced. The duration and intensity of light exposure was related as one of the most important factors.
