Trace metal exposure of soil bacteria depends on their position in the soil matrix

Micropores and biofilms of soils may protect bacteria against chemical stress, predation, and competition phenomena, explaining the great diversity and robustness of soil microbial communities and functions. We used sequential dispersion/density gradient centrifugation to separate free and loosely attached cells (FLA) from strongly attached cells (SA). The two fractions of the soils communities were investigated along a Zn and Cd pollution gradient, and the pollution-induced trace metal community tolerance (PICT) for SA and FLA was analyzed. FLA had developed a strong PICT in response to the 80 years of Zn and Cd pollution, whereas SA was virtually unaffected. It appears that the position of SA in biofilms and micropores has effectively protected them against toxic metal concentrations. The estimated free ion activity showed that the Cd activity was too low to reach toxic levels (PICT(cd) was probably caused by Zn). In contrast, the estimated Zn ion activity was close to a critical level, and could have caused the observed PICT(Zn) in FLA, at least if temporal/ spatial fluctuations of soil pH are taken into account. Such fluctuations could also explain the protection of SA as a result of diffusion constraints; which would be of little help under constant conditions because chemical equilibrium would be reached throughout.     

Effect of abomasal infusions of geometric isomers of 10,12 conjugated linoleic acid on milk fat synthesis in dairy cows

The trans-10, cis-12 isomer of conjugated linoleic acid (CLA) decreases TAG accumulation in 3T3-L1 adipocytes, reduces lipid accretion in growing animals, and inhibits milk fat synthesis in lactating mammals. However, there is evidence to suggest that other FA may also exert antilipogenic effects. In the current experiment, the effects of geometric isomers of 10,12 CLA on milk fat synthesis were examined using four Holstein-British Friesian cows in a 4×4 Latin Square experiment with 14-d periods. Treatments consisted of abomasal infusions of skim milk, or skim milk containing trans-10, cis-12 CLA (T1), trans-10, trans-12 CLA (T2), or a mixture of predominantly 10,12 isomers containing (g/100 g) trans-10, cis-12 (35.0), cis-10, trans-12 (23.2), trans-10, trans-12 (14.9), and cis-10, cis-12 (5.1). CLA supplements were prepared from purified ethyl linoleate and infused as nonesterified FA. Infusions were conducted over a 4-d period with a 10-d interval between treatments and targeted to deliver 4.5 g/d of 10,12 CLA isomers. Compared with the control, trans-10, trans-12 CLA had no effect (P>0.05) on milk fat yield, whereas treatments T1 and T3 depressed (P<0.05) milk fat content (19.8 and 22.9%, respectively) and decreased milk fat output (20.8 and 21.3%, respectively). Comparable reductions in milk fat synthesis to 4.14 and 1.80 g trans-10, cis-12/d supplied by treatments T1 and T3 indicate that other 10,12 geometric isomers of CLA have the potential to exert antilipogenic effects. The relative abundance of cis-10, trans-12 CLA in treatment T3 and the low transfer efficiency of this isomer into milk suggest that cis-10, trans-12 CLA was the active component.     

Bayesian Rating Curve Inference as a Streamflow Data Quality Assessment Tool

A streamflow time-series is normally obtained by transforming a time-series of recorded stage to discharge using an estimated rating curve. The accuracy of this streamflow time-series depends on the characteristics of the available stage-discharge measurements used to fit the rating curve. The Norwegian Water Resources and Energy Directorate (NVE) has developed a method based on rating curve uncertainty for performing objective quality assessment of streamflow time-series. The method, which is based on a Bayesian statistical framework, uses the available stage-discharge measurements and the corresponding stage time-series to derive statistics utilised for a quality assurance of the streamflow time-series. Nearly one thousand streamflow time-series periods have been classified using the method. This paper presents the results.     

Post‐installation adaptation of offshore wind turbine controls

The cost of offshore wind energy can be reduced by incorporating control strategies to reduce the support structures' load effects into the structural design process. While effective in reducing the cost of support structures, load‐reducing controls produce potentially costly side effects in other wind turbine components and subsystems. This paper proposes a methodology to mitigate these side effects at the wind farm level. The interaction between the foundation and the surrounding soil is a major source of uncertainty in estimating the safety margins of support structures. The safety margins are generally closely correlated with the modal properties (natural frequencies, damping ratios). This admits the possibility of using modal identification techniques to reassess the structural safety after installing and commissioning the wind farm. Since design standards require conservative design margins, the post‐installation safety assessment is likely to reveal better than expected structural safety performance. Thus, if load‐reducing controls have been adopted in the structural design process, it is likely permissible to reduce the use of these during actual operation. Here, the probabilistic outcome of such a two‐stage controls adaptation is analyzed. The analysis considers the structural design of a 10 MW monopile offshore wind turbine under uncertainty in the site‐specific soil conditions. Two control strategies are considered in separate analyses: (a) tower feedback control to increase the support structure's fatigue life and (b) peak shaving to increase the support structure's serviceability capacity. The results show that a post‐installation adaptation can reduce the farm‐level side‐effects of load‐reducing controls by up to an order of magnitude.     

The role of hydrogen in the transition from a petroleum economy to a low-carbon society

A radical decarbonization pathway for the Norwegian society towards 2050 is presented. The paper focuses on the role of hydrogen in the transition, when present Norwegian petroleum export is gradually phased out. The study is in line with EU initiatives to secure cooperation opportunities with neighbouring countries to establish an international hydrogen market. Three analytical perspectives are combined. The first uses energy models to investigate the role of hydrogen in an energy and power market perspective, without considering hydrogen export. The second, uses an economic equilibrium model to examine the potential role of hydrogen export in value creation. The third analysis is a socio-technical case study on the drivers and barriers for hydrogen production in Norway. Main conclusions are that access to renewable power and hydrogen are prerequisites for decarbonization of transport and industrial sectors in Norway, and that hydrogen is a key to maintain a high level of economic activity. Structural changes in the economy, impacts of new technologies, and key enablers and barriers in this transition are discussed.     

Dynamic changes of taste experiences in wine and cheese combinations

The ideal cheese and wine combination might be relatively subjective, depending on personal preference, context factors, previous knowledge and experience of food and wine. The aim of this study was to (I) explore consumer liking for wine and cheese pairs; to (II) explore whether either wine or cheese dominates a combination and to (III) understand the relationship between consumer liking and the dynamic taste experience. Consumer testing was performed in a restaurant setting where 45 consumers evaluated liking and dominance of combinations of cheese and wine as a part of a conference lunch. In a laboratory, Temporal Dominance of Sensation (TDS) was used to analyse the dynamic responses of five wines and Roquefort Société tasted in a mixed tasting. Results show significant differences between the wines for dominance and liking for the wines and cheese. A sweet and fruity dessert wine together with the cheese scored high for liking and no dominance was indicated of either wine or cheese. TDS is found to be a useful method to provide additional information about sensory attributes that give a high liking score, showing the dynamic in the eating process.     

Visualization of sensory profiling data for performance monitoring

Simple graphical techniques can be utilized to investigate the performance of individual assessors and to detect individual differences among assessors in a sensory panel. By visualizing different type of information in a set of various plots the panel leader can extract relevant information without the need of extensive knowledge in statistics. The joint information content gained from the plots can then be used as a basis for selective training in order to improve performance of single assessors and the panel as a whole.