Survival analysis applied to genetic evaluation for female fertility in dairy cattle

The objective of this research was to study whether survival analysis results in a more accurate genetic evaluation for female fertility traits compared with the usual methodology based on linear models. The fertility trait studied was interval between calving and last insemination. A stochastic simulation describing the reproductive cycle of first-parity cows was done, in which true breeding values for conception rate were created. A model containing effects of sire and herd was used both with survival analysis and with mixed linear model analysis to predict sire breeding values. Correlations between true breeding values for conception rate and breeding values for calving to last insemination predicted by the best survival analysis model or the best linear model were 0.77 and 0.68, respectively. The results showed that when pregnancy status is known, survival analysis is a better method than linear models for genetic evaluation of conception rate when using observations on the interval between calving and last insemination.     

Modelling aspects for finite element analysis of ship vibration

The paper describes the present state-of-the-art in analyses of ship vibration and elaborates on the difficulties regarding the finite element modelling.Some suggestions to enable better modelling of the structure, dependent on the aims of the analyses, the accuracy of input data, time and cost are given.It is shown that the main resonant frequencies of global and local structures may be predicted with sufficient accuracy, and a good indication of the forced response level may be obtained at the design stage.     

Mechanisms of weight maintenance under high- and low-protein, low-glycaemic index diets

Scope: Weight maintenance after intended weight loss is a challenge in an obesogenic environment. In a large multicentre dietary intervention study (DiOGenes), it has recently been demonstrated that a high‐protein/low‐glycaemic index (HP/LGI) diet was slightly more efficient in maintaining weight loss than low‐protein/LGI or high‐GI (LP/LGI or HGI) diets. Here, we use a proteomic approach to assess the molecular mechanisms behind this positive effect. Methods and results: A subset of the most successful (weight loser, n=12) and unsuccessful (weight re‐gainer, n=12) individuals consuming the LGI diets with either high‐ or low‐protein content (HP or LP/LGI), following an initial calorie deficit run‐in weight loss phase, were analyzed at the plasma protein level. Proteomic analysis revealed 18 proteins regulated after 6 months of the dietary weight maintenance phase. Furthermore, 12 proteins were significantly regulated as a function of success rate under an HP diet, arising as candidate biomarkers of mechanisms of successful weight maintenance under an HP/LGI diet. Pregnancy‐zone protein (PZP) and protein S (PROS1) were revealed as novel biomarkers of weight maintenance showing opposite effects. Conclusion: Semantic network analysis of the 12 regulated proteins revealed that under an HP/LGI an anti‐atherogenic effect and alterations of fat metabolism were associated with the success of maintaining the initial weight loss.     

Structural changes of casein micelles in a rennin gradient film with simultaneous consideration of the film morphology

The effect of rennin on the micelle structure and microstructure of casein films was investigated with micro-beam grazing incidence small angle X-ray scattering and optical microscopy. Size distributions of casein micelles and colloidal calcium phosphate particles were determined as a function of rennin concentration within a rennin gradient film. While the size of the casein micelles decreased with increasing rennin concentration, the size of the colloidal calcium phosphate clusters remained constant. In accordance with a first-order enzyme reaction mechanism, the rennin-induced decay of the micellar sizes could be well described by an exponential function. Two distinct film morphologies at high and low rennin concentration were observed. At intermediate rennin concentration a two-phase surface structure was found, in which both film morphologies coexisted. The conclusions drawn on the behaviour of casein micelles in films can generally be applied to the rennin-induced changes in casein micelles in bulk solutions.     

Processing and analytical characterisation of pulp-enriched cloudy apple juices

Pulp-enriched cloudy apple juices were manufactured from two apple varieties by blending of apple puree with natural cloudy apple juice in order to enrich bioactive secondary plant substances. Finishing of the puree with a 0.6-mm mesh screen and final product homogenisation revealed as the optimum processing technology for the novel 100% fruit beverage. The presence of large particles originating from the puree prevented long-term cloud stability, but due to the proportion of cloud-stable juice a complete phase separation did not occur. Optimal drinkability was achieved at a viscosity of 11.5 mPa s. Polyphenol compositions and concentrations were determined by means of RP-HPLC/PDA. The results ranged from 109 to 610 mg/l. All samples showed the typical polyphenol pattern of apples with dominating hydroxycinnamic acids followed by flavanols and flavonols. The puree addition to the cloudy apple juices increased the polyphenol concentrations by average 100%. Relatively, the highest increase could be observed for dimeric procyanidins. Different technological variants did not affect significantly the polyphenol concentrations. The dietary fibre contents of the pulp-enriched cloudy apple juices ranged from 5.8 to 9.4 g/l.     

The significance of the North Atlantic Oscillation (NAO) for sea-salt episodes and acidification-related effects in Norwegian rivers

Acidification of Norwegian surface waters, as indicated by elevated concentrations of sulfate and a corresponding reduction in acid neutralizing capacity and pH, is a result of emission and subsequent deposition of sulfur and nitrogen compounds. Episodic sea-salt deposition during severe weather conditions may increase the effects of acidification by mobilizing more toxic aluminum during such episodes. Changes in climatic conditions may increase the frequency and strength of storms along the coast thus interacting with acidification effects on chemistry and biota. We found that the North Atlantic Oscillation (NAO) is linked to sea-salt deposition and sea-salt induced water chemistry effects in five rivers. Particularly, toxic levels of aluminum in all rivers were significantly correlated with higher NAO index values. Further, temporal trends were studied by comparing tendencies for selected statistical indices (i.e. frequency distributions) with time. The selected indices exhibited strong correlations between the NAO index, sea-salt deposition and river data such as chloride, pH and inorganic monomeric aluminum, pointing at the influence of North Atlantic climate variability on water chemistry and water toxicity. The potentially toxic effects of sea-salt deposition in rivers seem to be reduced as the acidification is reduced. This suggests that sea-salt episodes have to increase in strength in order to give the same potential negative biological effects in the future, if acid deposition is further reduced. More extreme winter precipitation events have been predicted in the northwest of Europe as a result of climate change. If this change will be associated with more severe sea-salt episodes is yet unknown.     

The presence of Penicillium and Penicillium mycotoxins in food wastes

A total of 97 samples (48 summer and 49 winter) of food waste from private households were investigated for Penicillium and for mycotoxins. Twenty-five Penicillium species were isolated and Penicillium crustosum, Penicillium brevicompactum, Penicillium chrysogenum, Penicillium expansum, Penicillium roqueforti, Penicillium spinulosum, Penicillium viridicatum, Penicillium commune, Penicillium citrinum and Penicillium solitum were, in decreasing order, the most frequently identified species. Mycotoxins produced by several of these species, including mycophenolic acid, roquefortine C, penitrems A-F and thomitrems A and E, were detected. Of the 48 summer samples, 36 were severely infected and contained more than 10(5) colony forming units (CFU) Penicillium/g sample. The levels of mycotoxins in these samples were in the range 75-19000 microg/kg mycophenolic acid, 40-920 microg/kg roquefortine C, 35-7500 microg/kg penitrem A, 20-2100 microg/kg thomitrem A and 20-3300 microg/kg thomitrem E. Of the 49 winter samples, only one was found to contain mycophenolic acid (4800 microg/kg) and roquefortine C (190 microg/kg), and this sample was severely infected with P. roqueforti. Thirty samples of food waste collected from the food manufacturing industry were also investigated. The number of Penicillium in these samples was between 10(5) and 10(6) colony forming units (CFU)/g sample. Seven of these samples contained mycophenolic acid ranging from 50 to 600 microg/kg and three of these samples also contained roquefortine C in the range 100-250 microg/kg.