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排序方式: 共有51条查询结果,搜索用时 31 毫秒
21.
This study analysed meat consumption patterns among Finnish consumers, considering both stated past changes and intended future changes. Consumer segments with different patterns of and reasons for change were identified. Latent class analysis revealed six consumer clusters that formed three major cluster blocks. The first block, comprising 48% of the consumers, had established consumption patterns and no intentions to change them. In the second block, with 13% of the consumers, consumption patterns had already shifted towards more vegetables and less meat. The third block, with 39% of the consumers, was identified to be in the middle of a change with a general tendency to reduce the use of meat and increase the use of vegetables. Although the environmental effects of meat and animal welfare issues were important reasons for change in some clusters, healthiness was the most salient stated reason for changing consumption habits. 相似文献
22.
Eija Hyyti-Trees Ulrike Lyhs Hannu Korkeala Johanna Bjrkroth 《International journal of food microbiology》1999,50(3):338-219
Eighteen previously characterised Lactobacillus sakei strains exhibiting varying slime production capabilities in vacuum-packaged meat products were analysed using repetitive element sequence-based PCR (rep-PCR). The single primers BOXA1R and RW3A and the primer pair REP1R-Dt and REP2R-Dt were evaluated for their applicability in L. sakei genotyping. The five different patterns produced by RW3A were the least useful, with the discriminatory power equal to ribotyping. BOXA1R and REP–primer pair both produced six different banding patterns and the combination of these results yielded seven different rep-types. Rep-PCR was concluded to have approximately the same discriminatory power as randomly amplified polymorphic DNA (RAPD) analysis, but was inferior to pulsed-field gel electrophoresis (PFGE). However, if the results of rep-PCR and RAPD were combined, the discrimination was comparable to PFGE, with the exception that within Ribogroup I non-slime-producing strains were indistinguishable from weak slime producers. It was concluded that the combination of the two PCR-based typing techniques, rep-PCR and RAPD, would be a valuable tool in large scale contamination studies at meat processing plants, since results can be obtained rapidly with fewer isolates needing further analysis by PFGE. 相似文献
23.
Jorma Hls Kari Koski Ralf-Johan Lamminmki Eija Silynoja Przemysaw Dere Wiesaw Strk 《Journal of Alloys and Compounds》1997,250(1-2):370-374
The formation of cation solid solution in the (La1−xGdx)OCl:Eu3+ (0≤xGd≤1; ΔxGd=0.1) series was studied by photoluminescence spectroscopy. The luminescence from the 5D0–2 to the 7F0–4 levels of the Eu3+ ion in the (La1−xGdx)OCl series was recorded at 77 K by using argon ion laser excitation (457.9 nm). The interpretation of the spectra according to the C4v site symmetry of the Eu3+ ion in the tetragonal PbFCl-type structure yielded nearly complete sets (18 to 19 levels) for the 7F0–4 levels. Simulations of the Stark level schemes were carried out with the aid of a phenomenological c.f. theory utilizing the five non-zero c.f. Bqk parameters (B02, B04, B44, B06 and B46) allowed for the C4v site symmetry. By using the calculated c.f. parameter sets a quantitative measure was obtained to monitor the formation of cation solid solutions. The strength of the c.f. effect was estimated with the c.f. strength parameters S and Sk (k=2, 4 and 6). The c.f. parameter sets reproduced the experimental 7FJ (J=0–4) energy level schemes with the rms deviations between 4 and 11 cm−1. The individual parameters as well as the c.f. strength parameters were found to evolve in a smooth manner indicating complete solid solubility in the (La1−xGdx)OCl series. Some local distortions from the C4v symmetry — probably of long range—leading to the splitting of the 7F1 doubly degenerate E level were observed, however. 相似文献
24.
In Chlamydomonas reinhardtii, mutants defective in the cytochrome pathway of respiration lack the capacity to grow under heterotrophic conditions (in darkness on acetate). In the dark- strain duM18, a + 1 T addition in a run of four Ts, located at codon 145 of the mitochondrial cox1 gene encoding subunit I of cytochrome c oxidase, is responsible for the mutant phenotype. A leaky revertant (su11) that grows heterotrophically at a lower rate than wild-type cells was isolated from dum18. Its respiration sensitivity to cyanide was low and its cytochrome c oxidase activity was only 4% of that of the wild-type enzyme. Meiotic progeny obtained from crosses between revertant and wild-type cells inherited the phenotype of the mt- parent, showing that the suppressor mutation, like dum18 itself, is located in the mitochondrial genome. In order to map the su11 mutation relative to dum18, a recombinational analysis was performed on the diploid progeny. It demonstrated that su11 was very closely linked to the dum18 mutation less than 20-30 bp away. The cox1 gene of the su11 revertant was then sequenced. In addition to the + 1 T frameshift mutation still present at codon 145, an A-->C substitution was found at codon 146, leading to the replacement of a glutamic acid by an alanine in the polypeptide chain. No other mutations were detected in the cox1 coding sequence. As the new GCG codon (Ala) created at position 146 is very seldom used in the mitochondrial genome of C. reinhardtii, we suggest that the partial frameshift suppression by the nearby substitution is due to an occasional abnormal translocation of the ribosome (+ 1 base shift) facilitated both by the run of Ts and the low level of weak interaction of alanyl-tRNA. 相似文献
25.
To elucidate the epidemiology of human T-lymphotropic virus type I (HTLV-I) associated uveitis (HAU), a multicenter case-control study was carried out by the collaboration of university hospitals throughout Kyushu and Okinawa in southwestern Japan where HTLV-I is endemic; two institutions in the non-endemic metropolitan areas of Tokyo and Yokohama also participated. A total of 426 cases of endogenous uveitis were registered during the five-month period between September 1992 and January 1993; the etiology and clinical entity of about half of the cases were definable, and for the remaining half were unknown. Assessment of antibodies to HTLV-I revealed that the group of entity-undefined uveitis cases showed a significantly high seroprevalence when compared with age- and sex-matched controls. Estimate of the risk of HTLV-I provided supportive evidence for its etiologic contribution to a considerable proportion of hitherto undefined isolated uveitis cases. The prevalence of HAU thus defined was found to correspond to the seroprevalence in the relevant areas. Occasional cases were found among residents in the nonendemic metropolitan areas who had moved from the endemic areas. 相似文献
26.
Martikkala E Veltel S Kirjavainen J Rozwandowicz-Jansen A Lamminmäki U Hänninen P Härmä H 《Analytical chemistry》2011,83(24):9230-9233
Mutations of the small GTP-binding protein Ras have been commonly found in tumors, and Ras oncogenes have been established to be involved in the early steps of cancerogenesis. The detection of Ras activity is critical in the determination of the cell signaling events controlling cell growth and differentiation. Therefore, development of improved methods for primary screening of novel potential drugs that target small GTPase or their regulators and their signaling pathways is important. Several assays have been developed for small GTPases studies, but all these methods have limitations for a high-throughput screening (HTS) use. Multiple steps including separation, use of radioactive labels or time-consuming immunoblotting, and a need of large quantities of purified proteins are decreasing the user-friendliness of these methods. Here, we have developed a homogeneous H-Ras activity assay based on a single-label utilizing the homogeneous quenching resonance energy transfer technique (QRET). In the QRET method, the binding of a terbium-labeled GTP (Tb-GTP) to small GTPase protein H-Ras protects the signal of the label from quenching, whereas the signal of the nonbound fraction of Tb-GTP is quenched by a soluble quencher. This enables a rapid determination of the changes in the activity status of Ras. The assay optimization showed that only 60 nM concentration of purified H-Ras protein was needed. The functionality of the assay was proved by detecting the effect of H-Ras guanine nucleotide exchange factor, Son of Sevenless. The signal-to-background ratio up to 7.7 was achieved with an average assay coefficient of variation of 9.1%. The use of a low concentration of purified protein is desirable and the signal-to-background ratio of 3.4 was achieved in the assay at a concentration of 60 nM for H-Ras and SOS proteins. The need of only one labeled molecule and the ability to decrease the quantities of purified proteins used in the experiments are valuable qualities in HTS showing the potential of the QRET method. 相似文献
27.
Pia Laine Eija ToppinenReetta Kivelä Veli-Matti TaavitsainenOssi Knuutila Tuula Sontag-StrohmKirsi Jouppila Jussi Loponen 《Journal of food engineering》2011,104(4):538-547
The objective of this study was to develop an oil in water (o/w) emulsion using modified oat bran (MOB). Test emulsions containing 5% rapeseed oil were prepared by varying the content of MOB and maintaining the solid content constant (20%) by using corn syrup solids (DE34) as filler. A central composite (CC) design was applied as a tool to obtain a stable and low viscosity emulsion. The effect of concentration of MOB, homogenization pressure and homogenization time on the emulsion stability (at 25 °C for 26 h), viscosity and particle size were determined. The concentration of MOB in the recipe significantly influenced the emulsion properties whereas the homogenization pressure and the homogenization time had no statistically significant influence on the emulsion properties. Further experiments, however, showed that increasing the homogenization pressure decreased the emulsion viscosity. Emulsions prepared using a MOB concentration of 1.55% and homogenized at 60 MPa for 10 min, exhibited excellent stability, low viscosity, small enough mean particle size and narrow particle size distribution. Modified oat bran containing deamidated oat protein possesses an excellent capability to form stable emulsions which might be suitable for microencapsulation. 相似文献
28.
User needs for location-aware mobile services 总被引:2,自引:2,他引:2
Eija Kaasinen 《Personal and Ubiquitous Computing》2003,7(1):70-79
Mobile contexts of use vary a lot, and may even be continuously changing during use. The context is much more than location, but its other elements are still difficult to identify or measure. Location information is becoming an integral part of different mobile devices. Current mobile services can be enhanced with location-aware features, thus providing the user with a smooth transition towards context-aware services. Potential application fields can be found in areas such as travel information, shopping, entertainment, event information and different mobile professions. This paper studies location-aware mobile services from the user's point of view. The paper draws conclusions about key issues related to user needs, based on user interviews, laboratory and field evaluations with users, and expert evaluations of location-aware services. The user needs are presented under five main themes: topical and comprehensive contents, smooth user interaction, personal and user-generated contents, seamless service entities and privacy issues. 相似文献
29.
Helena Karasti Karen S. Baker Eija Halkola 《Computer Supported Cooperative Work (CSCW)》2006,15(4):321-358
This paper aims to enrich the current understanding of data curation prevalent in e-Science by drawing on an ethnographic study of one of the longest-running efforts at long-term consistent data collection with open data sharing in an environment of interdisciplinary collaboration. In such a context we identify a set of salient characteristics of ecological research and data that shape the data stewardship approach of the Long Term Ecological Research (LTER) network. We describe the actual practices through which LTER information managers attend to the extended temporal scale of long-term research and data sets both through data care work and information infrastructure development. We discuss the issues of long-term and continuity that represent central challenges for data curation and stewardship. We argue for more efforts to be directed to understanding what is at stake with a long-term perspective and differing temporal scales as well as to studying actual practices of data curation and stewardship in order to provide more coherent understandings of e-Science solutions and technologies. 相似文献
30.