Microbial diversity in different compartments of an aquaponics system.

Aquaponics is a solution for sustainable production of fish and plants in a single semi-closed system, where nutrient-rich water from the aquaculture provides nutrients for plant growth. We examined the microbial communities within an experimental aquaponics system. Whereas the fish feces contained a separate community dominated by bacteria of the genus Cetobacterium, the samples from plant roots, biofilter, and periphyton were more similar to each other, while the communities were more diverse. Detailed examination of the data gave the first indications to functional groups of organisms in the different compartments of the aquaponic system. As other nitrifiers other than members of the genus Nitrospira were only present at low numbers, it was anticipated that Nitrospirae may perform the nitrification process in the biofilm.

Impact of observation on disposition of elderly patients presenting to emergency departments with non-specific complaints.

BACKGROUND: Emergency Departments (EDs) have to cope with an increasing number of elderly patients, often presenting with non-specific complaints (NSC), such as generalized weakness. Acute morbidity requiring early intervention is present in the majority of patients with NSC. Therefore, an early and optimal disposition plan is crucial. The objective of this study was to prospectively study the disposition process of patients presenting to the ED with NSC. METHODS: For two years, all patients presenting with NSC presenting to an urban ED were screened and consecutively included. The initial disposition plan was compared to the effective transfer after observation. Optimal disposition was defined as a high accuracy regarding disposition of patients with acute morbidity to an internal medicine ward. RESULTS: The final study population consisted of 669 patients with NSC. Admission to internal medicine increased from 297 (44%) planned admissions to 388 (58%) effective admissions after observation. Conversely, transfers to geriatric community hospitals and discharges decreased from the initially planned 372 (56%) patients to 281 (42%) effectively transferred and discharged patients. The accuracy regarding disposition of patients with acute morbidity increased from 53% to 68% after observation. CONCLUSION: Disposition planning in patients with NSC improves after observation, if defined by the accuracy regarding hospitalization of patients with acute morbidity. Further research should focus on risk stratification tools for timely disposition planning in order to reduce high admission rates for patients without acute morbidity and high readmission rates for discharged patients with non-specific complaints.

Screening, detection and management of delirium in the emergency department - a pilot study on the feasibility of a new algorithm for use in older emergency department patients: the modified Confusion Assessment Method for the Emergency Department (mCAM-ED).

BACKGROUND: Delirium in emergency department (ED) patients occurs frequently and often remains unrecognized. Most instruments for delirium detection are complex and therefore unfeasible for the ED. The aims of this pilot study were first, to confirm our hypothesis that there is an unmet need for formal delirium assessment by comparing informal delirium ratings of ED staff with formal delirium assessments performed by trained research assistants. Second, to test the feasibility of an algorithm for delirium screening, detection and management, which includes the newly developed modified Confusion Assessment Method for the Emergency Department (mCAM-ED) at the ED bedside. Third, to test interrater reliability of the mCAM-ED. METHODS: This was a pilot study with a pre-post-test design with two data collection periods before and after the implementation of the algorithm. Consecutive ED patients aged 65 years and older were screened and assessed in the ED of a tertiary care center by trained research assistants. The delirium detection rate of informal ratings by nurses and physicians was compared with the standardized mCAM-ED assessment performed by the research assistants. To show the feasibility at the ED bedside, defined as adherence of ED staff to the algorithm, only post-test data were used. Additionally, the ED nurses' assessments were analyzed qualitatively. To investigate the agreement between research assistants and the reference standard, the two data sets were combined. RESULTS: In total, 207 patients were included in this study. We found that informal delirium assessment was inappropriate, even after a teaching intervention: Sensitivity of nurses to detect delirium without formal assessment was 0.27 pretest and 0.40 post-test, whilst sensitivity of physicians' informal rating was 0.45 pre-test and 0.6 post-test. ED staff demonstrated high adherence to the algorithm (76.5%). Research assistants assessing delirium with the mCAM-ED demonstrated a high agreement compared to the reference standard (kappa = 0.729). CONCLUSIONS: Informal assessment of delirium is inadequate. The mCAM-ED proved to be useful at the ED bedside. Performance criteria need to be tested in further studies. The mCAM-ED may contribute to early identification of delirious ED patients.

Elimination of phenols, ammonia and cyanide in wash water from biomass gasification, and nitrogen recycling using planted trickling filters.

Trickling filters were used to treat wash water from a wood gasifier. This wash water contained toxic substances such as ammonium, cyanide, phenols, and PAH. The goal was to develop a system that degraded toxic substances, and achieved full nitrification of ammonia. A 1 kW model wood gasifier plant delivered wash water for the experiments, which was standardised to a conductivity of 3 mS/cm by dilution. Toxicity was assessed by bacterial luminescence detection, germination test with cress (Lepidium sativum), and pot plants cultivated in a hydroponic setup irrigated continuously with the wastewater. Treatment experiments were done in both planted and unplanted trickling filters. Plant yield was similar to conventional hydroponic production systems. The trickling filters achieved complete detoxification of phenol, PAH and cyanide as well as full nitrification. The specific elimination rates were 100 g m(-3) Leca d(-1) for phenols and 90 g m(-3) Leca d(-1) for ammonium in planted systems. In unplanted trickling filters circulated for 63 h, phenol concentration decreased from 83.5 mg/L to 2.5 mg/L and cyanide concentration from 0.32 mg/L to 0.02 mg/L. PAH concentrations were reduced from 3,050 microg/L to 0.89 microg/L within 68 days. The assays demonstrated the feasibility of using the technique to construct a treatment system in a partially closed circulation for gasifier wash water. The principal advantage is to convert toxic effluents from biomass gasifiers into a non-toxic, nitrogen-rich fertiliser water, enabling subsequent use in plant production and thus income generation. However, the questions of long-term performance and possible accumulation of phenols and heavy metals in the produce still have to be studied.