Optimal Sorting of Raw Materials, Based on the Predicted End-Product Quality

Raw material variation is one of the most important factors causing unstable end-product quality. A methodology for sorting raw materials into homogenous groups with constant and optimized processing within each group is presented. The sorting criterion is based on the squared distance between the predicted response and its target value. The raw materials are split into homogenous categories by a partitioning algorithm related to the fuzzy-c-means algorithm. The method has been tested for raw material properties in one and two dimensions and with different degrees of fuzziness. The method shows good flexibility and can also be used with a penalty function penalizing unfavorable process settings.     

A Further Empirical Investigation of the Relationship Between MRE and Project Size

The mean magnitude of relative error, MMRE, is the de facto standard evaluation criterion to assess the accuracy of software project prediction models. The fundamental metric of MMRE is MRE, a relative residual error. For MMRE to be a meaningful summary statistic, it is a necessary, but not sufficient, condition that MRE and project size are uncorrelated. Except for two previous conference studies done by the same authors, it has never been empirically validated that MRE and project size really are uncorrelated. In this paper, we extend the previous studies using the same data sets as before: Albrecht, Kemerer, Finnish, DMR and Accenture-ERP. Unlike the previous studies, we plot MRE against the predicted effort rather than against the actual effort and, in so doing, we obtain very different results from the previous studies. The results of this study suggest that MRE and project size are uncorrelated, which apparently is contradictory to the previous results where we found a negative correlation. The explanation for these seemingly contradictory results is presented in this study.     

Effects of different dietary fat levels in cage‐fed Atlantic mackerel (Scomber scombrus)

In wild Atlantic mackerel, Scomber scombrus, the lipid content of the lateral muscle varies according to the season from around 30% in autumn to less than 5% in spring. To be able to offer mackerel with optimal quality on the market during spring or early summer after overwintering, it is necessary that the muscle lipid content is close to 30%, which is favoured by the customers. Wild caught mackerel were kept in salmon cages fed a high energy (300 g fat kg^{– 1} ) salmon diet rich in n‐3 polyunsaturated fatty acids from October 1997 to April 1998. Fish were submerged at 20—40 m at a temperature above 5 °C from January until April. Then the fish were brought to the surface and randomly divided into three duplicate groups, i.e., non‐fed, 150 g fat kg ^{– 1}, and 300 g fat kg ^{– 1} and kept until August 1998. The mortality was very low and the body weight doubled concomitant with an increased muscle lipid content from 19.5% to 30.9% during the first six months. Both groups receiving feed further increased the body weight and muscle lipid content at the same magnitude towards the end of the experiment. During the first six months the cross sectional area (CSA) of red muscle fibres increased 3.3fold and this size was maintained throughout the experiment. In contrast, in non‐fed mackerel the increase in CSA of red muscle fibres was 1.5fold. White muscle fibres revealed a much weaker response in fed mackerel and were not affected in mackerel deprived of feed. In wild mackerel the fatty acid oxidation (β‐oxidation) capacity dominated in the red part of the lateral muscle. During the winter an increased β‐oxidation capacity was found in heart and liver, whereas both red and white part of the lateral muscle showed a low fatty acid catabolism. In contrast, during summer red and white part of the lateral muscle possessed high β‐oxidation capacities, particularly in high energy‐fed and non‐fed mackerel. It is concluded that it is possible to feed captive mackerel during the winter and produce mackerel with a high quality for the market in early spring.     

The urban landscape as affordance for adolescents’ everyday physical activity

This study explores factors in the physical outdoor environment of the urban landscape that promote or hinder adolescents’ physical activity (PA). The analysis was inspired by Gibson’s affordance concept. The study combines actual use with potential affordances in neighbourhoods to generate special classes of actualised affordances. Two Norwegian school districts and their local neighbourhoods in different landscapes were selected as case areas. The patterns of adolescents’ everyday leisure-time activity were recorded using ‘children’s tracks’ methodology. Landscape characterisation connected the activity patterns to the physical structure of the landscape. Our study suggests that urban landscape structure is associated with PA patterns and adolescents’ choice of activity types. Our results confirm previous studies as regards the importance of neighbourhood design and facilities for PA in promoting such activity.     

Air quality and microbiologic contamination in operating theatres

The present study concerns the air quality and microbiological contamination in two newly built operating theatres; one with laminar air flow (LAF) equipment for cardio-thoracic operations, and one with conventional ventilation for urological operations. Both theatres had an identical number of air exchanges (17/h), identical microclimatic conditions and they employed the same cleaning procedures. In the LAF-ventilated operating theatre bacterial contamination of the air was effectively reduced to less than 10 colony-forming units (CFU)/m3 in all 125 samples (1 m3 per sample) tested. In most samples, 118/125, the bacterial count was less than 5 CFU/m3, despite the presence of ten persons. The conventionally ventilated theatre reached values up to 120 CFU/m3 during the most active period of the day when approximately seven persons were present. The LAF ventilation reduced both the content of particles in the air and contamination by bacteria on the floor. In both theatres cleaning procedures had only a low impact on CFU in the air and on the floor. The use of diathermia markedly increased the level of small particles in the air, and this may influence the air quality in the operating theatres.     

Controlled human wood smoke exposure: oxidative stress, inflammation and microvascular function

Background

Due to the rising use of nanomaterials (NMs), there is concern that NMs induce undesirable biological effects because of their unique physicochemical properties. Recently, we reported that amorphous silica nanoparticles (nSPs), which are one of the most widely used NMs, can penetrate the skin barrier and induce various biological effects, including an immune-modulating effect. Thus, it should be clarified whether nSPs can be a risk factor for the aggravation of skin immune diseases. Thus, in this study, we investigated the relationship between the size of SPs and adjuvant activity using a model for atopic dermatitis.

Results

We investigated the effects of nSPs on the AD induced by intradermaly injected-mite antigen Dermatophagoides pteronyssinus (Dp) in NC/Nga mice. Ear thickness measurements and histopathological analysis revealed that a combined injection of amorphous silica particles (SPs) and Dp induced aggravation of AD in an SP size-dependent manner compared to that of Dp alone. In particular, aggravation was observed remarkably in nSP-injected groups. Furthermore, these effects were correlated with the excessive induction of total IgE and a stronger systemic Th2 response. We demonstrated that these results are associated with the induction of IL-18 and thymic stromal lymphopoietin (TSLP) in the skin lesions.

Conclusions

A particle size reduction in silica particles enhanced IL-18 and TSLP production, which leads to systemic Th2 response and aggravation of AD-like skin lesions as induced by Dp antigen treatment. We believe that appropriate regulation of nanoparticle physicochemical properties, including sizes, is a critical determinant for the design of safer forms of NMs.     

Trans-Membrane Uptake and Intracellular Metabolism of Fatty Acids in Atlantic Salmon (<Emphasis Type="Italic">Salmo salar</Emphasis> L.) Hepatocytes

To elucidate if the trans-membrane uptake of fatty acids is protein-mediated, the uptake of oleic acid (18:1n-9), linoleic acid (18:2n-6), alpha-linolenic acid (18:3n-3), eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) was investigated in vitro in Atlantic salmon (Salmo salar L.) primary hepatocytes. Firstly, optimal fatty acid incubation time and concentration were established for trans-membrane 18:n-9 uptake. Based on saturation kinetics, a 2-h incubation time and 37.5 μM were used for the following experiments. Secondly, in order to identify whether trans-membrane fatty acid uptake in hepatocytes was mainly passive or protein mediated, hepatocytes were pre-incubated with membrane protein inhibitors followed by 2 h of incubation with [1-¹⁴C] labelled 18:1n-9, 18:2n-6, 18:3n-3, 20:5n-3 and 22:6n-3. Fatty acid uptake into hepatocytes was highest with 20:5n-3 and 22:6n-3 and lowest with 18:1n-9. Phloretin was the most potent fatty acid uptake inhibitor, inhibiting uptake in the following order: 20:5n-3 > 18:3n-3 = 22:6n-3 > 18:2n-6 > 18:1n-9. The uptake of FA in Atlantic salmon hepatocytes seem to be due to both saturable and inhibitable protein mediated uptake, as well as passive uptake processes with more unsaturated and long fatty acids (20:n-3 > 22:6n-3 = 18:3n-3 > 18:2n-6) being more dependent on membrane protein mediated uptake compared to 18:1n-9.     

β-Oxidation of 18∶3n−3 in atlantic salmon (<Emphasis Type="Italic">Salmo salar</Emphasis> L.) hepatocytes treated with different fatty acids

To study whether Atlantic salmon β-oxidation was affected by dietary FA composition, an in vitro study with primary hepatocytes was undertaken. Isolated hepatocyte cultures were stimulated with either 16∶0, 18∶1n−9, 18∶2n−6, 18∶3n−3, 20∶5n−3, or 22∶6n−3 in triplicate for 24 h. In addition, a control was included where no FA stimulation was performed, also in triplicate. After stimulation, radiolabeled [1-¹⁴C]18∶3n−3 was added and the cells were incubated for 2 h at 20°C. The cells were then harvested, and radioactivity was determined in the acid-soluble part of the cells and medium, i.e., the end products of the β-oxidation pathway. Specific β-oxidation activity was significantly higher in hepatocytes stimulated with 18∶3n−3. Further, when taking into account the amount of radiolabeled [1-¹⁴C]18∶3n−3 taken up by the cells—the relative amount of β-oxidized [1-¹⁴C]18∶3n−3 of the total FA taken up by the hepatocytes—no significant differences were found. Thus, the regulation of β-oxidation activity in the primary Atlantic salmon hepatocytes seems to be at the level of FA uptake and transport into the cell. This in vitro study shows that the catabolism processes in salmon hepatocytes are affected by the FA available and probably already regulated at the level of FA uptake.