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Kaarina Aarnisalo Kaija Tallavaara Gun Wirtanen Riitta Maijala Laura Raaska 《Food Control》2006,17(12):1001-1011
The hygienic working practices of the maintenance personnel as well as the hygiene of the equipment in the food industry were investigated with questionnaires and microbial surveys. The protective clothing, washing of hands and tools as well as avoiding foreign bodies left on the production lines should be targeted when the hygienic working practices are developed for maintenance personnel. Based on the questionnaire to food processors, packaging machines, conveyers, dispensers, slicing and cooling machines were considered the most problematic pieces of equipment hygienically mainly because of poor hygienic design. In order to improve food safety, both the training of maintenance personnel in food hygiene and equipment design should be more emphasised. 相似文献
3.
Tanja Kolli Katariina Rahkamaa-Tolonen Ulla Lassi Auli Savimki Riitta L. Keiski 《Catalysis Today》2005,100(3-4):303-307
In this study, Pd/Al2O3 and Pd/BaO/Al2O3 metallic monoliths were used to investigate the effect of BaO in C2H4 and CO oxidation as well as in NO reduction. A FT-IR gas analyser was used to study the activity of the catalysts. Several activity experiments carried out with dissimilar feedstreams revealed that BaO enhances CO and C2H4 oxidation as well as NO reduction reactions in rich conditions. This effect is due to BaO, which causes a decrease in the ethene poisoning of palladium. In lean conditions BaO is present in the form of Ba(OH)2 which reacts with oxidised NO releasing water. Therefore, NO was stored during the lean reaction. 相似文献
4.
I Vauhkonen L Niskanen M Ryyn?nen R Voutilainen J Partanen J T?yry M Mercuri R Rauramaa M Uusitupa 《Canadian Metallurgical Quarterly》1997,14(9):748-756
We analysed a well-characterized group of 83 patients (43 men, 40 women; mean age +/- SEM: 65.5 +/- 0.6 years at the 10-year examination) with non-insulin-dependent (Type 2) diabetes mellitus (NIDDM) and in 123 control subjects (56 men, 67 women; mean age +/- 0.9 years) retrospectively for the relationship of apolipoprotein E (apo E) genotypes (E2/3, E3/3 vs E3/4, E4/4) to the incidence of clinical macrovascular disease and its risk factors and the incidence of microvascular complications of diabetes during the first 10 years of NIDDM, as well as carotid intima-media thickness measured by B-mode ultrasound at the 10-year examination. In patients with NIDDM, apo E4 genotype showed no relationship to clinical events or carotid intima-media thickness. However, in the control subjects with apo E4, the incidence of non-fatal myocardial infarction during the follow-up was increased (apo E4 positivity: 17.1%; apo E4 negativity 5.1%; p = 0.035) and they had higher common carotid intima-media thickness than those with apo E2/3 or apo E3/3 (1.15 +/- 0.05 mm vs 1.01 +/- 0.03 mm, p = 0.008). Apo E genotype groups showed no relationship to microvascular complications of diabetes, although control subjects with apo E4 positivity showed a higher frequency of microalbuminuria than those lacking apo E4. We conclude that apo E4 was a marker of vascular disease and increased atherosclerosis in non-diabetic subjects, whereas in the diabetic patients these relationships were absent. It is likely that NIDDM per se influences the vascular risk so overwhelmingly that the effects of other risk factors are obscured. 相似文献
5.
Intercellular communication is needed for both the generation of the mesodermal germ layer and its division into distinct subpopulations. To dissect the functions of fibroblast growth factor receptor-1 (FGFR1) during mouse gastrulation as well as to gain insights into its possible roles during later embryonic development, we have introduced specific mutations into the Fgfr1 locus by gene targeting. Our results show functional dominance of one of the receptor isoforms and suggest a function for the autophosphorylation of site Y766 in the negative regulation of FGFR1 activity. Y766F and hypomorphic mutations in Fgfr1 generate opposite phenotypes in terms of homeotic vertebral transformations, suggesting a role for FGFR1 in patterning the embryonic anteriorposterior axis by way of regulation of Hox gene activity. 相似文献
6.
Riitta Kettunen Sanna Saarnio Pertti J. Martikainen Jouko Silvola 《Nutrient Cycling in Agroecosystems》2006,74(2):175-189
The effects of elevated atmospheric CO2 concentration on soil moisture, N2O fluxes, and biomass production of Phleum pratense were studied in the laboratory. Farmed peat and sandy soil mesocosms sown with P. pratense were fertilized with a commercial fertilizer. In peat soil 10 g N m−2 of commercial fertilizer were added and in sandy soil 15 g N m−2. In both experiments, soil moisture was regulated with deionized water; 18 mesocosms were tended to keep equally moist, and
the other 18 were watered with equal amounts of water. Nine mesocosms from both watering treatments were grown under ambient
(360 μmol mol−1) CO2 concentration and the remaining nine under doubled (720 μmol mol−1) CO2. N2O efflux was monitored using a closed chamber technique and a gas chromatograph. The elevated supply of CO2 increased production of above- and belowground biomass, soil moisture and N2O fluxes, but decreased the total N content in the aboveground biomass, especially for the sandy soil. In similar water levels,
N2O efflux from the sandy soil was the same magnitude as that from the peat soil. In addition to moisture, N availability was
the main limiting factor for N2O production, but C availability also seemed to regulate the denitrification activity. In addition to an increase in C availability
the increase in the N2O efflux under the raised CO2 concentration also required a simultaneous increase in soil moisture. 相似文献
7.
Katariina Rahkamaa-Tolonen Teuvo Maunula Mari Lomma Mika Huuhtanen Riitta L. Keiski 《Catalysis Today》2005,100(3-4):217-222
The activity of fresh and hydrothermally aged zeolite-based catalysts in the NH3-selective catalytic reduction (SCR) reaction with excess of oxygen were studied. In addition, the effect of NO2 in the gas feed as well as the acidity of the catalysts for the SCR activity was investigated. The studied catalysts were hydrogen, copper, iron and silver ion exchanged ZSM-5, mordenite, beta, ferrierite, and Y-zeolites. The investigation verifies that the zeolite-based catalysts are very promising for the ammonia SCR reaction. Especially, the activity at low and high temperatures was higher than the activity of commercial vanadia-based catalysts. From the studied catalysts, Fe-beta was the most potential one. The presence of NO2 in the inlet flow enhanced significantly the catalytic activity of fresh and hydrothermally aged zeolite catalysts. This suggests that the oxidation of NO to NO2 is probably the rate-determining step for the SCR reaction. 相似文献
8.
A new type of a swinging interferometer, the carousel interferometer, is presented, and its properties are studied and compared with other swinging interferometers. The new interferometer is built with five plane mirrors. The optical path difference is accomplished by rotation of a system that consists of four mirrors. The modulation is almost independent of the scanning of the interferometer. It is not sensitive to external perturbations such as bending or other deformations of the mount. The construction is very compact. Because of its stability and low cost it is very applicable to small Fourier-transform spectrometers for any wave-number region from the far infrared down to the ultraviolet. 相似文献
9.
J Rossinen J Partanen P Koskinen L Toivonen M Kupari MS Nieminen 《Canadian Metallurgical Quarterly》1996,75(6):563-567
PURPOSE: The purpose was to determine tumor neovascularisation via colour-coded Doppler (duplex) sonography and the "power mode", both visually and quantitatively, by means of videodensitometry. MATERIAL AND METHODS: 6 VX2 tumours of 4 to 11 mm size were implanted in 4 rabbits at various sites. The colour-coded duplex sonography and the new sonographic power technique were tested before and after having injected a new contrast medium (SH U 616A). RESULTS: If no contrast medium was injected, tumour neovascularisation was identified in only 50% of the cases. Injection of contrast medium increased signal intensity three to fourfold with all examined tumors. Combined use of the sonographic method by the power technique with injection of contrast medium is outstandingly suitable for tumor vessel imaging even of small tumors, as these initial results seem to show. CONCLUSION: If these results are corroborated by further studies, contrast-medium supported sonographic technique may possibly become established as an alternative method to other imaging procedures. 相似文献
10.
Françoise Martz Laura Jaakola Riitta Julkunen-Tiitto Sari Stark 《Journal of chemical ecology》2010,36(9):1017-1028
Bilberry is a characteristic field layer species in the boreal forests and is an important forage plant for herbivores of
the North European ecosystem. Bilberry leaves contain high levels of phenolic compounds, especially hydroxycinnamic acids,
flavonols, catechins, and proanthocyanidins. We investigated the phenolic composition of bilberry leaves in two studies, one
following foliar development in forest and open areas, and the other along a wide geographical gradient from south to north
boreal forests in Finland. An analysis of bilberry leaves collected in open and forest areas showed that major phenolic changes
appeared in the first stages of leaf development, but, most importantly, synthesis and accumulation of flavonoids was delayed
in the forest compared to the high light sites. Sampling along a geographical gradient in the boreal zone indicated that leaves
from higher latitudes and higher altitudes had greater soluble phenolic and flavonol levels, higher antioxidant capacity,
and lower contents of chlorogenic acid derivatives. The ecological significance of the results is discussed. 相似文献