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71.
Hely Tuorila Irena Matuszewska Ulla Hellemann Anna-Maija Lampi 《Food quality and preference》1989,1(4-5):157-162
Ten dairy fat or margarine-based spreads with 40, 60 or 80% fat, were compared pairwise for their similarity/dissimilarity. The sensory profiles, fatty acid compositions and NaCl contents were also determined. In multidimensional scaling analysis, the three dimensions obtained distinguished between 1) the 80% spreads containing mainly dairy fat vs. others, 2) the spreads containing 40% fat vs. others, and 3) certain individual samples. Polynsaturated vs. saturated fatty acids described dimension I (butter/notbutter), whereas the monounsaturated fatty acids were related to dimensions II and III. The P/S ratios ranged from 0.03 to 2.09. From a sensory viewpoint the major choice offered to the consumers seems to be the one between traditional spreads containing 80% dairy fat and all the remaining spreads. 相似文献
72.
Nicklas Raun Jacobsen Peter Møller Keld Alstrup Jensen Ulla Vogel Ole Ladefoged Steffen Loft Håkan Wallin 《Particle and fibre toxicology》2009,6(1):2-17
Background
The toxic and inflammatory potential of 5 different types of nanoparticles were studied in a sensitive model for pulmonary effects in apolipoprotein E knockout mice (ApoE-/-). We studied the effects instillation or inhalation Printex 90 of carbon black (CB) and compared CB instillation in ApoE-/- and C57 mice. Three and 24 h after pulmonary exposure, inflammation was assessed by mRNA levels of cytokines in lung tissue, cell composition, genotoxicity, protein and lactate dehydrogenase activity in broncho-alveolar lavage (BAL) fluid. 相似文献73.
Comparing two burnout interventions: Perceived job control mediates decreases in burnout. 总被引:1,自引:0,他引:1
H?tinen Marja; Kinnunen Ulla; Pekkonen Mika; Kalimo Raija 《Canadian Metallurgical Quarterly》2007,14(3):227
This quasi-experimental study compared the effects of two rehabilitation interventions on burnout and perceived job conditions during a 1-year intervention among female white-collar workers. The participatory intervention (n = 20), involving rehabilitation activities that focused on the individual as well as on individual-organizational levels, assessed exhaustion, cynicism and perceived job control during a 1-year period. Increased job control served as a mechanism through which exhaustion and cynicism decreased in this intervention. The traditional intervention (n = 32), involving rehabilitation activities focusing mainly on the individual level, resulted in a reduction in time pressures during one year. Furthermore, both interventions improved perceived workplace climate. Compared to the traditional approach, the participatory intervention was a more effective strategy for treating burnout. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Future air traffic management concepts envisage shared decision-making responsibilities between controllers and pilots, necessitating that controllers be supported by automated decision aids. Even as automation tools are being introduced, however, their impact on the air traffic controller is not well understood. The present experiments examined the effects of an aircraft-to-aircraft conflict decision aid on performance and mental workload of experienced, full-performance level controllers in a simulated Free Flight environment. Performance was examined with both reliable (Experiment 1) and inaccurate automation (Experiment 2). The aid improved controller performance and reduced mental workload when it functioned reliably. However, detection of a particular conflict was better under manual conditions than under automated conditions when the automation was imperfect. Potential or actual applications of the results include the design of automation and procedures for future air traffic control systems. 相似文献
75.
Mykkänen J Tohka J Luoma J Ruotsalainen U 《Computer methods and programs in biomedicine》2005,79(1):1-17
In this study, we propose and evaluate new methods for automatic extraction of the brain surface and the mid-sagittal plane from functional positron emission tomography (PET) images. Designing methods for these segmentation tasks is challenging because the spatial distribution of intensity values in a PET image depends on the applied radiopharmaceutical and the contrast to noise ratio in a PET image is typically low. We extracted the brain surface with a deformable model which is based on a global optimization algorithm. The global optimization allows reliable automation of the extraction task. Based on the extracted brain surface, the mid-sagittal plane was determined. The method was tested with the image of the Hoffman brain phantom (FDG) and the images from the brain studies with the FDG (17 images) and the C11-Raclopride tracers (4 images). In addition to the brain surfaces, we applied the deformable model for extraction of the coarse cortical structure based on the tracer uptake from FDG-PET brain images. The proposed segmentation methods provide a promising direction for automatic processing and analysis of PET brain images. 相似文献
76.
Ulla Fiedler 《Journal of the American Oil Chemists' Society》1974,51(3):101-103
The AOCS official method for the determination of peroxide values of fats and oils has been modified to perform more precise
analyses, especially in the range of extremely low values (peroxide value <1). In the newly developed method presented here,
the final titrimetric step of an iodometric method has been replaced by an electrochemical technique, based upon coulometric
reduction of the iodine at an electrode maintained at a controlled potential. Using this method peroxide values down to 0.06
were determined with reasonable precision. Finally, the influence of different parameters on the peroxide value obtained was
investigated. 相似文献
77.
Aerosol lidar intercomparison in the framework of the EARLINET project. 2. Aerosol backscatter algorithms 总被引:1,自引:0,他引:1
Böckmann C Wandinger U Ansmann A Bösenberg J Amiridis V Boselli A Delaval A De Tomasi F Frioud M Grigorov IV Hågård A Horvat M Iarlori M Komguem L Kreipl S Larchevêque G Matthias V Papayannis A Pappalardo G Rocadenbosch F Rodrigues JA Schneider J Shcherbakov V Wiegner M 《Applied optics》2004,43(4):977-989
An intercomparison of aerosol backscatter lidar algorithms was performed in 2001 within the framework of the European Aerosol Research Lidar Network to Establish an Aerosol Climatology (EARLINET). The objective of this research was to test the correctness of the algorithms and the influence of the lidar ratio used by the various lidar teams involved in the EARLINET for calculation of backscatter-coefficient profiles from the lidar signals. The exercise consisted of processing synthetic lidar signals of various degrees of difficulty. One of these profiles contained height-dependent lidar ratios to test the vertical influence of those profiles on the various retrieval algorithms. Furthermore, a realistic incomplete overlap of laser beam and receiver field of view was introduced to remind the teams to take great care in the nearest range to the lidar. The intercomparison was performed in three stages with increasing knowledge on the input parameters. First, only the lidar signals were distributed; this is the most realistic stage. Afterward the lidar ratio profiles and the reference values at calibration height were provided. The unknown height-dependent lidar ratio had the largest influence on the retrieval, whereas the unknown reference value was of minor importance. These results show the necessity of making additional independent measurements, which can provide us with a suitable approximation of the lidar ratio. The final stage proves in general, that the data evaluation schemes of the different groups of lidar systems work well. 相似文献
78.
79.
M?kikangas Anne; Feldt Taru; Kinnunen Ulla; Tolvanen Asko; Kinnunen Marja-Liisa; Pulkkinen Lea 《Canadian Metallurgical Quarterly》2006,18(4):444
This study provides new knowledge about the factor structure of the 12-item General Health Questionnaire (GHQ-12; D. Goldberg, 1972) through the application of confirmatory factor analysis to longitudinal data, thereby enabling investigation of the factor structure, its invariance across time, and the rank-order stability of the factors. Two community-based longitudinal adult samples with 1-year (n = 640) and 6-year (n = 330) follow-up times were studied. As a result, the correlated 3-factor model (i.e., Anxiety/Depression, Social Dysfunction, and Loss of Confidence) showed a better fit with both samples than the alternative models. The correlated 3-factor structure was also relatively invariant across time in both samples, indicating that the scale has good construct validity. The rank-order stabilities of the factors were low across time, which suggests that the GHQ-12 measures temporal mental state. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.