700 research outputs found
Long-term P weathering and recent N deposition control contemporary plant-soil C, N, and P
Models are needed to understand how plant-soil nutrient stores and fluxes have responded to the last two centuries of widespread anthropogenic nutrient pollution and predict future change. These models need to integrate across carbon, nitrogen, and phosphorus (C, N, and P) cycles and simulate changes over suitable timescales using available driving data. It is also vital that they are constrainable against observed data to provide confidence in their outputs. To date, no models address all of these requirements. To meet this need, a new model, N14CP, is introduced, which is initially applied to Northern Hemisphere temperate and boreal ecosystems over the Holocene. N14CP is parameterized and tested using 88 northern Europe plot-scale studies, providing the most robust test of such a model to date. The model simulates long-term P weathering, based on the assumption of a starting pool of weatherable P (Pweath0, g m−2), which is gradually transformed into organic and sorbed pools. Nitrogen fixation (and consequently primary production) is made dependent on available P. In the absence of knowledge about the spatial variability of Pweath0, N14CP produces good average soil and plant variables but cannot simulate variations among sites. Allowing Pweath0 to vary between sites improves soil C, N, and P results greatly, suggesting that contemporary soil C, N, and P are sensitive to long-term P weathering. Most sites were found to be N limited. Anthropogenic N deposition since 1800 was calculated to have increased plant biomass substantially, in agreement with observations and consequently increased soil carbon pools
Bioimpedance-based authentication of defrosted versus fresh pork at the end of refrigerated shelf life
publishedVersio
Photochromic mechanism in oxygen-containing yttrium hydride thin films: An optical perspective
Oxygen-containing yttrium hydride thin films exhibit photochromic behavior: Transparent thin films reversibly switch from a transparent state to a photodarkened state after being illuminated with UV or blue light. From optical spectrophotometry and ellipsometry measurements of the transparent state and photodarkened state, it is concluded that the photochromic effect can be explained by the gradual growth, under illumination, of metallic domains within the initial wide-band-gap semiconducting lattice. This conclusion is supported by Raman measurements
Effects of high-strength fecal sludge in wastewater stabilization ponds: Port-au-Prince, Haiti
At the request of the Haitian National Directorate for Potable Water and Sanitation (DINEPA), the Centers for Disease Control and Prevention (CDC) performed an evaluation of the Morne à Cabri wastewater stabilization pond (WSP) serving the Port-au-Prince metro area. In order to assess the performance of the facility, samples were taken from faecal sludge trucks entering the system to characterize influents and from each process unit to assess the reduction of BOD5 (Biochemical Oxygen Demand) and other parameters. Although design expectations were met for BOD5 removal, the system was overloaded with organics and solids, leading to quick sludge accumulation. More monitoring is required, and possible design modifications should be made to reduce the quantity of high-strength faecal sludge entering the system
Recommended from our members
The effects of a dialogue-based intervention to promote psychosocial well-being after stroke: a randomized controlled trial
Objective:
To evaluate the effect of a dialogue-based intervention targeting psychosocial well-being at 12 months post-stroke.
Design:
Multicenter, prospective, randomized, assessor-blinded, controlled trial with two parallel groups.
Setting:
Community.
Subjects:
Three-hundred and twenty-two adults (⩾18 years) with stroke within the last four weeks were randomly allocated into intervention group (n = 166) or control group (n = 156).
Interventions:
The intervention group received a dialogue-based intervention to promote psychosocial well-being, comprising eight individual 1–1½ hour sessions delivered during the first six months post-stroke.
Main measures:
The primary outcome measure was the General Health Questionnaire-28 (GHQ-28). Secondary outcome measures included the Stroke and Aphasia Quality of Life Scale-39g, the Sense of Coherence scale, and the Yale Brown single-item questionnaire.
Results:
The mean (SD) age of the participants was 66.8 (12.1) years in the intervention group and 65.7 (13.3) years in the control group. At 12 months post-stroke, the mean (SE) GHQ-28 score was 20.6 (0.84) in the intervention group and 19.9 (0.85) in the control group. There were no between-group differences in psychosocial well-being at 12 months post-stroke (mean difference: −0.74, 95% confidence interval (CI): −3.08, 1.60). The secondary outcomes showed no statistically significant between-group difference in health-related quality of life, sense of coherence, or depression at 12 months.
Conclusion:
The results of this trial did not demonstrate lower levels of emotional distress and anxiety or higher levels of health-related quality of life in the intervention group (dialogue-based intervention) as compared to the control group (usual care) at 12 months post-stroke
The bodily presence of significant others: Intensive care patients' experiences in a situation of critical illness
This study is about intensive care patients and the bodily presence of significant others. The aim of the study is to inquire and understand the patients experience of the body in relation to their significant others during critical illness. Open, unstructured, in-depth interviews with six former intensive care patients provide the data for the study. The phenomenological–hermeneutical analysis points to a theme among ICU patients' experience of conflict between proximity and distance during the bodily presence of their relations. Patients experience different and conflicting forms of responses to the presence of their significant others. Patients experience significant positive confirmation but also negation through this presence. In the ICU situation, the reactions of significant others appear difficult to deal with, yet the physical presence is significant for establishing a sense of affinity. Patients seek to take some responsibility for themselves as well as for their relatives, and are met with a whole spectrum of reactions. Intensive care patients experience the need to be actively, physically present, which often creates sharp opposition between their personal needs and the needs of their significant others for active participation
- …