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1.
The aim of this paper is to introduce the concept of boundary objects in order to better understand the role of objects in participatory ergonomics (PE) design processes. The research question is: What characterizes boundary objects in PE processes? Based on two case studies, we identify eight characteristics of boundary objects and their use, which make them particularly useful in PE design processes. These characteristics go beyond the object itself and extend into the context of their use. We argue that the selection of boundary objects in PE processes is of great importance, since different objects enable workers’ participation and collaborative design in different ways. The framework developed may serve to provide criteria to guide practitioners and intervention researchers in the selection of objects to facilitate a PE process. The paper concludes with a list of recommendations for ergonomic practitioners that are based on the framework.  相似文献   
2.
There is some evidence from epidemiology that intake of n-3 polyunsaturated fatty acids (PUFA) from seafood may protect against coronary artery disease (CAD). This hypothesis is further supported from animal data showing a beneficial effect of n-3 PUFA on thrombosis and atherosclerosis in animals fed fish oils in most, but not all, studies. There are several mechanisms by which an increased intake of marine n-3 PUFA may protect against CAD; the most universal finding is a reduction of plasma triglycerides. It is puzzling, however, that a very low amount of n-3 PUFA, with no known beneficial biochemical effects, seems to be cardioprotective. It has therefore been of paramount interest to perform clinical trials. Such evidence and trials are discussed in later chapters, and the results have been very encouraging.  相似文献   
3.
Pressure-treatment at 300 MPa of minced chicken breast meat did not induce significant lipid oxidation during chill storage for up to 15 days, while pressure-treatment at 600 and 800 MPa enhanced formation of secondary lipid oxidation products measured as thiobarbituric acid reactive substances. However, a waste product from industrial tomato paste production was found to yield efficient protection against lipid oxidation in pressurized chicken meat. Addition of 0.30% tomato waste or of 0.10% final tomato paste to minced meat led to a lag phase of 6 days for formation of secondary oxidation products in meat pressure treated at 600 MPa. The waste product seemed special efficient in protecting chicken meat pressurized at 800 MPa, as a notably lower rate of formation of secondary oxidation products was found. Flavonoids washed out with the waste fraction may be more efficient as antioxidant than the other phenolics or carotenoids present in the other paste processing fractions. Addition of tomato paste fractions did not influence radical formation measured by electron spin resonance spectroscopy and the tomato waste is considered to be effective as antioxidant at subsequent reactions leading to secondary lipid oxidation products.  相似文献   
4.
Twelve dressing systems made by varying protein type, oil level, CaCl2, NaCl, and sucrose, were examined using scanning electron microscopy. Images from the 12 systems were quantitatively analysed using methods of feature extraction. These methods were based on vectorisations of the images followed by principal component analysis on the extracted vectors. These techniques were used to examine the reproducibility of the acquired images as well as to relate the images to rheologic and sensory texture parameters. Two feature extraction methods were used: the angle measure technique (AMT) and the absolute difference method (ABDF). The ABDF method used fewer principal components to extract information from images relevant to the complex modulus/sensory viscosity of the system, but the information seemed equally well preserved by the two-feature extraction methods. The AMT was more efficient in classifying the images with respect to protein type. A fair correlation between images and complex modulus was obtained (R=0.73). It is suggested that a better correlation might be obtained by adding more systems, increasing the number of areas imaged for each system as well as avoiding systems of low viscosity.  相似文献   
5.
Ripening of barrel-salted herring (Clupea harengus) is evaluated by the use of fluorescence spectroscopy and protein determinations. During ripening, protein degradation takes place in the herring and protein is extracted into the brine. The present study aims at identifying parameters which are correlated to the ripening characteristics of barrel-salted herring and which can provide a better understanding of the ripening process. Front face fluorescence landscapes were obtained by measuring directly on the brine from barrel-salted herring. These data were analyzed by parallel factor analysis (PARAFAC), which revealed four fluorophores, tryptophan (two states), vitamin B6 and riboflavin. All four parameters showed an increase in concentration during the storage period corresponding to an increase in protein content that varied from 3 g/100 g at day 60 to 5 g/100 g after 277 days of storage. It was not possible to see a difference in the development of the four fluorophores during the ripening period. The protein content was predicted from the fluorescence landscapes by partial least squares (PLS). The use of unfolded fluorescence spectra gave an RMSECV of 0.26 g/100 g and a correlation between the measured protein content and the predicted values of 0.86.  相似文献   
6.
Many real-time problems require assessment of the location of a moving platform with respect to a fixed or time varying set of objects. Examples of such problems are robots performing precision movement in a dense object space or low flying aircraft over enemy territory. The method described in this paper permits quick assessment of relative locations to two- or three-dimensional rectangular shaped objects with respect to an arbitrary number of points and subsequently to a real or fictive line of sight. The relative location assessment can be performed at a rate of up to 5 ns/data point/object and the line intersect evaluation at 5–500 ns/line/object dependent upon the geometry.Both the relative assessment algorithm and the intersect algorithm have been implemented in a small hardware unit called the TIGER, Three-dimensional Intersect & Geometrical Evaluation in Real-time, that can be incorporated in unmanned as well as manned systems in space, under water, and avionics. All quoted performance data is based upon analysis in three dimensional Cartesian space unless otherwise stated.  相似文献   
7.
The effect of high hydrostatic pressure on turbidity of skim milk was measured in situ together with casein micelle size distribution. High pressure (HP) treatment reduced the turbidity of milk with a stronger pressure dependency between 50 and 300 MPa when the temperature was decreased from 20 to 5 °C, while at 30 °C (50–150 MPa) turbidity exceeded that of untreated milk. At 250 and 300 MPa turbidity decreased extremely. During pressurization of milk at 250 and 300 MPa, the turbidity initially decreased, but treatments longer than 10 min increased the turbidity progressively, indicating that re-association followed dissociation of casein micelles. Especially at 40 °C and at 250 and 300 MPa, the turbidity increased beyond untreated milk. Dynamic light scattering was used to investigate casein micelle sizes in milk immediately after long time (up to 4 h) pressurization at 250 and 300 MPa and casein micelle size distributions were bimodal with micelle sizes markedly smaller and markedly larger than those of untreated milk. Pressure modified casein micelles present after treatment of milk at 250 and 300 MPa were concluded to be highly unstable, since the larger micelles induced by pressure showed marked changes toward smaller particle sizes in milk left at ambient pressure.  相似文献   
8.
Enzymes are used widely as effective additives to laundry detergents for improved detergency on soiled fabric. They have potential for cleaning of “dingy” soils in addition to the stain removal benefits. Cellulases contribute to the overall whiteness of cotton-containing textiles when worn and washed several times, meaning that their cleaning is not associated solely with the regions characterized by high amounts of fatty material, e.g., collars/cuffs. The focus of this research was to study further the performance of cellulases for whiteness maintenance of cotton textiles. Cotton garments soiled by multiple wearings and washed using a cellulase treatment were evaluated using scanning electron microscopy and X-ray microanalysis. Washing with cellulase significantly reduced residual soil concentrations at all morphological locations on the cotton fibers for each set of matched garments. The relative concentrations of residual soil on the fabrics agreed well with the color differences measured at 440 nm. Cellulase affected removal of oily soil from within the cotton fiber secondary wall, resulting in residual oil concentrations similar to those at morphological locations that were more accessible for detergency such as the fiber surface and crenulations. Since cellulase hydrolyzes cellulose, it was expected that the effect would be within the structure of the fiber, i.e., secondary wall. The cellulase effect on redeposition garments was similar to garments worn and washed. As with lipase, the enhanced removal of soil from the interior bulk structure of the cotton fiber with use of cellulase is unique, since most other detergent components have higher functionality at fabric, yarn, and fiber surfaces. We think that cellulase is functioning by hydrolyzing cellulose from the internal surfaces of fibrils within the secondary wall, opening up the pore structure for enhanced detergency and forming a new surface with each washing.  相似文献   
9.
The objective of this study was to evaluate the importance of geographic origin and grazing system for Norwegian and Italian consumers' probability of buying lamb meat. The study consisted of a qualitative part with focus groups followed up with a quantitative survey in each country. Included in the survey was a conjoint design with origin of the meat (Norway, Italy and New Zealand) and pasture (lowland pasture and mountain pasture) as factors, plus questions about consumers' motives underlying selection of food. Results from the study shows that country of origin is important for consumers' buying probability of lamb meat, in both countries domestic meat was preferred. In addition, a higher probability of buying meat from lamb grazing on mountain pasture than from lamb grazing on lowland pasture was identified. It is important for producers of lamb meat to increase the communication of these elements in a competitive national and international food market.  相似文献   
10.
Intake of fish and omega-3 (n-3) fatty acids is associated with a reduced concentration of plasma triacylglycerols (TAG) but the mechanisms are not fully clarified. Stearoyl-CoA desaturase-1 (SCD1) activity, governing TAG synthesis, is affected by n-3 fatty acids. Peripheral blood mononuclear cells (PBMC) display expression of genes involved in lipid metabolism. The aim of the present study was to estimate whether intake of lean and fatty fish would influence n-3 fatty acids composition in plasma phospholipids (PL), serum TAG, 18:1n-9/18:0 ratio in plasma PL, as well as PBMC gene expression of SCD1 and fatty acid synthase (FAS). Healthy males and females (n = 30), aged 20–40, consumed either 150 g of cod, salmon, or potato (control) daily for 15 days. During intervention docosahexaenoic acid (DHA, 22:6n-3) increased in the cod group (P < 0.05), while TAG concentration decreased (P < 0.05). In the salmon group both eicosapentaenoic acid (EPA, 20:5n-3) and DHA increased (P < 0.05) whereas TAG concentration and the 18:1n-9/18:0 ratio decreased (P < 0.05). Reduction of the 18:1n-9/18:0 ratio was associated with a corresponding lowering of TAG (P < 0.05) and an increase in EPA and DHA (P < 0.05). The mRNA levels of SCD1 and FAS in PBMC were not significantly altered after intake of cod or salmon when compared with the control group. In conclusion, both lean and fatty fish may lower TAG, possibly by reducing the 18:1n-9/18:0 ratio related to allosteric inhibition of SCD1 activity, rather than by influencing the synthesis of enzyme protein.  相似文献   
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