Mathematical model for energy and protein balance simulation in broilers

The authors used the empirical equations of mathematical modelling for the energy and protein balance simulation, with the view of calculating the body weight gain in broilers fed various diets. The results found by using the model were compared with the experimental data obtained by several authors. A standard deviation of +/- 1.20% and a mean error of +/- 0.28% and a mean error of +/- 0.28% which proved that the model average was a sufficient estimate of the experimental average were found. Furthermore, using the regression method, a significant correlation of variables was evidentiated.     

Use of cis-atracurium to maintain moderate neuromuscular blockade in experimental pigs

Objective

To determine the dose of cis-atracurium needed to produce a moderate neuromuscular blockade (NMB) in pigs.

Plant diversity enhances the reliability of belowground processes

Theory predicts that the probability that an ecosystem will provide a consistent level of functioning over a given unit of time, i.e. the reliability of ecosystem processes, should increase with species richness. There is growing evidence that plant diversity increases the temporal stability of productivity, but only a few studies have investigated its impact on the reliability of ecosystem processes, and information on whether this propagates to the belowground system is virtually lacking. Using a microcosm experiment with plant communities varying in species and functional group diversity and two decomposer groups (earthworms and Collembola) we investigated the effects of plant diversity on the reliability of the belowground system and vice versa, the effect of decomposers on the reliability of plant productivity. Generally, plant diversity increased the reliability of above- and belowground processes by significantly increasing the reliability of eight out of eleven measured ecosystem parameters (six out of nine belowground responses). Plant functional group diversity had a stronger stabilising effect than species richness on above- and belowground processes including plant shoot and total biomass, microbial basal respiration and Collembola densities. By contrast, in the presence of both decomposer groups the reliability of decomposer populations was reduced. The results indicate that plant diversity effects propagate into the belowground system and increase the reliability of belowground processes via more consistent plant derived belowground inputs.     

Leaf morphological and genetic differentiation between <Emphasis Type="Italic">Quercus robur</Emphasis> L. and its closest relative,the drought-tolerant <Emphasis Type="Italic">Quercus pedunculiflora</Emphasis> K. Koch

• Introduction  

The study of phenotypic and genetic differentiation between incipient species or species that have recently diverged provides insights into the evolutionary history of species complexes and may contribute to our understanding of how species will evolve in contrasting environmental conditions.     

Phosphorylation by cyclin B-Cdk underlies release of mitotic exit activator Cdc14 from the nucleolus

Budding yeast protein phosphatase Cdc14 is sequestered in the nucleolus in an inactive state during interphase by the anchor protein Net1. Upon entry into anaphase, the Cdc14 early anaphase release (FEAR) network initiates dispersal of active Cdc14 throughout the cell. We report that the FEARnetwork promotes phosphorylation of Net1 by cyclin-dependent kinase (Cdk) complexed with cyclin B1 or cyclin B2. These phosphorylations appear to be required for FEAR and sustain the proper timing of late mitotic events. Thus, a regulatory circuit exists to ensure that the arbiter of the mitotic state, Cdk, sets in motion events that culminate in exit from mitosis.     

Earthworms enhance plant regrowth in a grassland plant diversity gradient

Knowledge of the role of decomposers in the plant diversity–productivity relationship is scarce. In the framework of the Jena Experiment, we observed regrowth of grassland plant communities varying in plant species and functional group richness three weeks after mowing. We investigated earthworm subplots and subplots with reduced earthworm density in order to explore if earthworms enhance plant regrowth and if earthworm effects depend on plant diversity. Earthworms significantly enhanced each of the plant regrowth parameters (plant coverage and maximum and average height of the vegetation) suggesting that particularly fast growing species, such as grasses, benefit from earthworm activity. However, the average height of the vegetation was not affected in 16-species mixtures suggesting compensation of the impact of earthworms on plant regrowth in complex plant communities.     

Comparison of clinical effects of epidural levobupivacaine morphine versus bupivacaine morphine in dogs undergoing elective pelvic limb surgery

Objective

To evaluate the efficacy, in terms of the amount of rescue analgesia required, and the clinical usefulness of epidural injection of morphine with bupivacaine or levobupivacaine for elective pelvic limb surgery in dogs during a 24-hour perioperative period.

Plant community impacts on the structure of earthworm communities depend on season and change with time

Declining plant diversity potentially threatens essential ecosystem functions driven by the decomposer community, such as litter decomposition and nutrient cycling. Currently, there is no consensus on the interrelationships between plant diversity and decomposer performance and previous studies highlighted the urgent need for long-term experiments.In the Jena Experiment we investigated the long-term impacts of plant community characteristics on the structure of earthworm communities representing key decomposers in temperate grassland. We repeatedly sampled plots varying in plant species richness (1-16 species), plant functional group richness (1-4 groups), and presence of certain plant functional groups (grasses and legumes) three, four, and six years after establishment of the experiment in spring and autumn.The results show that earthworm performance is essentially driven by the presence of certain plant functional groups via a variety of mechanisms. Plant productivity (root biomass) explained most of the detrimental grass impacts (decrease in earthworm performance), while beneficial legume effects likely were linked to high quality inputs of plant residues (increase in earthworm performance). These impacts depended on the functional group of earthworms with the strongest effects on surface feeding anecic earthworms and minor effects on soil feeding endogeic species. Remarkably, effects of plant community characteristics on the composition and age structure of earthworm communities varied between seasons. Moreover, plant diversity effects reported by a former study decreased and detrimental effects of grasses increased with time.The results indicate that plant community characteristics, such as declining diversity, indeed affect the structure of earthworm communities; however, loss of key plant functional groups is likely to be more important than plant species number per se. However, in frequently disturbed ecosystems plant species richness might be important for the recovery and resilience of belowground functions. Moreover, the results accentuate the importance of long-term repeated measurements to fully appreciate the impacts of plant community composition and diversity on ecosystem properties. Single point observations may be misleading and potentially mask the complexity of above-belowground interrelationships.