Macrofaunal Functional Diversity Provides Resilience to Nutrient Enrichment in Coastal Sediments

The degradation of ecosystems is often associated with losses of large organisms and the concomitant losses of the ecological functions they mediate. Conversely, the resilience of ecosystems to stress is strongly influenced by faunal communities and their impacts on processes. Denitrification in coastal sediments is a process that may provide ecosystem resilience to eutrophication by removing excess bioavailable nitrogen. Here, we conducted a large-scale field experiment to test the effect of macrofaunal community composition on denitrification in response to two levels of nutrient enrichment at 28 sites across a biologically heterogeneous sandflat. After 7 weeks of enrichment, we measured denitrification enzyme activity (DEA) along with benthic macrofaunal community composition and environmental variables. We normalised treatment site specific DEA values by those in ambient sediments (DEACN) to reveal the underlying response across the heterogeneous landscape. Nutrient enrichment caused reductions in DEACN as well as functional changes in the community; these were both more pronounced under the highest level of nutrient loading (on average DEACN was reduced by 34%). The degree of suppression of DEACN following moderate nitrogen loading was mitigated by a key bioturbating species, but following high nitrogen loading (which reduced the key species density) the abundance and diversity of other nutrient processing species were the most important factors alleviating negative effects. This study provides a prime example of the context-dependent role of biodiversity in maintaining ecosystem functioning, underlining that different elements of biodiversity can become important as stress levels increase. Our results emphasise that management and conservation strategies require a real-world understanding of the community attributes that facilitate nutrient processing and maintain resilience in coastal ecosystems

Warmteoverdracht bij condensatie

Applied SciencesKramers Laboratorium voor Fysische Technologi

Beef Cow Milk Composition and Calf Scours

Information on milk composition and factors influencing milk nutrient concentrations in beef cows was very limited. This research studied colostrum, since scouring in beef calves often occurs the first few days after birth. The objectives of this research were to determine protein, milkfat and lactose composition of beef cow colostrum. to compare these factors in colostral samples drawn from cows fed hay and cows fed silage to determine the relationship between beef cow diet, beef cow colostral composition and the incidence of calf scours

Nutrient management regulations in The Netherlands - Discussion

ABSTRACT Background: Anesthesia groups may wish to decrease the supervision ratio for nontrainee providers. Because hospitals of fer many first-case starts and focus on starting these cases on time, the number of anesthesiologists needed is sensitive to this ratio. The number of operating rooms that an anesthesiologist can supervise concurrently is determined by the probability of multiple simultaneous critical portions of cases (i.e., requiring presence) and the availability of cross-coverage. A simulation study showed peak occurrence of critical portions during first cases, and frequent supervision lapses. These predictions were tested using real data from an anesthesia information manage ment system. Methods: The timing and duration of critical portions of cases were determined from 1 yr of data at a tertiary care hospital. The percentages of days with at least one supervi sion lapse occurring at supervision ratios between 1:1 and 1:3 were determined. Results: Even at a supervision ratio of 1:2, lapses occurred on 35% of days (lower 95% confidence limit = 30%). The peak incidence occurred before 8:00 AM, P < 0.0001 for the hypoth esis that most (i.e., >50%) lapses occurred before this time. The average time from operating room entry until ready for prep ping and draping (i.e., anesthesia release time) during first case starts was 22.2 min (95% confidence interval 21.8 -22.8 min). Conclusions: Decreasing the supervision ratio from 1:2 to 1:3 has a large effect on supervision lapses during first-cas

Prevention of venous thrombosis after an anterior cruciate ligament reconstruction: compression stockings alone vs. its combination with low molecular weight heparin

Optimising joint reconstruction management in arthritis and bone tumour patient