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81.
The hydrolysis of sunflower and soybean oil, catalyzed by two enzymes, non‐immobilized Candida rugosa and immobilized Candida antarctica lipase, was performed at atmospheric and high‐pressure. The results showed that at atmospheric pressure between 40 °C and 60 °C initial reaction rates were influenced by the temperature variation, as expected. Due to favorable physico‐chemical properties of dense gases as reaction media, hydrolysis of soybean oil was performed in non‐conventional solvents: in supercritical (SC) CO2 and near‐critical propane. In SC CO2 the activity of non‐immobilized Candida rugosa lipase decreased while the reaction rates of hydrolysis catalyzed by immobilized Candida antarctica lipase were 1.5‐fold higher than at atmospheric pressure. However, the reaction rates for the hydrolyses catalyzed by both lipases, were much higher in propane than at atmospheric pressure.  相似文献   
82.
Au nanoparticle chains embedded in helical Al2O3 nanotubes (“nanopeapods”) are synthesized by annealing carbon nanocoils coated with Au by sputtering and Al2O3 by atomic layer deposition. Regular spacing between nanoparticles with a sharp size distribution is achieved by fragmentation of the Au coating in agreement with the pitch of the nanocoils arising from three‐dimensional periodical topography of the carbon nanocoil templates. A strong plasmonic resonance behavior of the fabricated nanopeapods manifests itself in confocal laser scanning microscopy by a clear polarization contrast at red wavelengths, which is absent in the blue. Numerical simulations confirm an incisive resonance enhancement for longitudinal polarization and suggest the nanopeapods as promising candidates for highly efficient, ultrathin waveguides. The waveguiding properties of the nanopeapods are investigated by electron energy‐loss spectroscopy and energy‐filtered TEM imaging.  相似文献   
83.
The effects of added copper in the manufacture of Finnish Emmental cheese were studied. Consequently, cheeses were produced with or without the copper supplement and a facultative heterofermentative strain, Lactobacillus rhamnosus Lc705, which is currently utilized as a protective culture in large-scale manufacture in Finland. Cheeses were examined at 1, 7, 30, 60, and 90 d from the microbiological, chemical, and sensory points of view. Organic acid production was affected by the presence of copper in the cheeses. The addition of copper to cheesemilk increased the level of primary proteolysis and slowed secondary proteolysis as measured by nitrogen content in different extracts after citrate fractionation of cheeses, in pH 4.4-soluble nitrogen and 5% phosphotungstic acid-soluble nitrogen, respectively. The presence of copper appears to positively regulate the sensory characteristics of the cheese produced in our conditions; in particular, consistency was affected significantly. The role of the Lb. rhamnosus Lc705 protective strain has not been shown to have important effects on most of the parameters that influence the final quality of the cheeses. Although the traditional plating systems for revealing bacterial populations during cheese manufacture did not reveal any drastic differences caused by the presence of copper, the results from chemical and sensory analyses suggest that its use plays a significant role in the regulation of bacterial physiological and biochemical activities, which in turn affect the sensory quality of Emmental cheese.  相似文献   
84.
This paper focuses on the management of an industrial heritage site in Sweden, which local stakeholders and heritage planners have claimed to be successful. This status of excellence is investigated in relation to the general, county-wide applied heritage planning. The results show that key factors for successful management of the industrial heritage site are not related only to conservation work, but also to personal engagement, sense of responsibility, and well-being among participants. However, heritage planners generally lack methods to address immaterial values and socio-economic benefits of engaging in heritage activities, resulting in a separation between physical and communal aspects of heritage planning. The results highlight the issue of professional legitimacy and the challenges for heritage planners to address regional policy objectives, such as finding ways to utilise historic landscapes in destination-driven strategies and to simultaneously support civil engagement in heritage-related issues.  相似文献   
85.
The objective of this study was to determine the correlation between the results obtained with the ELISA technique for antibodies to Mycobacterium avium ssp. paratuberculosis in serum and bulk tank milk at the herd level. For this purpose, 203 samples of bulk tank milk were analyzed with 2 commercial ELISA from dairy herds with a prevalence of seropositive animals that was also determined. In regard to the reference test (results in blood serum), the sensitivity of the bulk tank milk test to detect high-positive herds (≥10% seroprevalence) ranged from 85.7 to 71.4%. The specificity to detect herds with no seropositive animals ranged from 70.5 to 53%. In a quantitative approach, Pearson correlation coefficients, reported as a measure of the linear association between herd seroprevalences and transformed optical density values recorded in bulk tank milk, were 0.39 and 0.54 for the studied ELISA. Although the test results were relatively fairly correlated with the within-herd prevalence, the practical utility of bulk tank milk testing for Mycobacterium avium ssp. paratuberculosis seems limited, especially regarding specificity.  相似文献   
86.
Wrens, Troglodytes troglodytesare highly polygynous passerines. Males build cock nests that are displayed to females and function as a mate-choice cue. Males with large numbers of nests are more likely to attract females than males with fewer nests. To be useful to females a cue used in mate choice must contain information. One way to evaluate the information content of such a cue may be to examine the factors that influence its size. The number of nests was predicted on territories with known building rates (immigration) and nest destruction rates (death) using an immigration-death function. This analysis suggested that if only building rate and destruction rates were considered then the number of nests on territories was consistently overestimated. In 1994 an experiment was conducted in which nest-site availability was manipulated. Males provided with additional nest sites built more nests and continued to build later in the year resulting in longer nest-building periods than controls. The converse was found when nest sites were experimentally removed. This suggested that the number of nests that could be constructed on a territory was limited by habitat structure. None of the morphological characters considered here significantly influenced the number of nests built by males. Therefore, the information content of this mate-choice cue will be primarily about characteristics of the habitat on the territory rather than characteristics of the male.1997The Association for the Study of Animal Behaviour  相似文献   
87.
PURPOSE: To compare spiral (SCT) and electron-beam CT (EBT) for the diagnosis of pulmonary embolism (PE). MATERIALS AND METHODS: From June 1997 to June 1998 188 patients with suspected acute or chronic thromboembolism of the pulmonary arteries were examined. A total of 108 patients were scanned using SCT and 80 patients using EBT. On each scanner two different scan protocols were evaluated. RESULTS: PE was diagnosed in 38 patients using EBT and in 49 patients using SCT. Especially with EBT, isolated peripheral emboli could be confidently diagnosed. When EBT and SCT were compared for the analysis of peripheral pulmonary arteries, some paracardiac segmental and subsegmental vessels were significantly better analyzable with EB. Additional or diseases other than PE were diagnosed in 112 patients. Other diagnoses included bronchial carcinoma and aortic dissection. CONCLUSIONS: Advanced CT scanning techniques allow the highly accurate diagnosis of central and peripheral PE. Other potentially life-threatening underlying diseases are also readily recognized.  相似文献   
88.
Macrophage scavenger receptors (MSR) are implicated in the development of atherosclerosis and amyloid b-protein deposition in Alzheimer's disease. However, histopathological studies of MSR expression in human tissues have been hampered by a lack of specific antibodies. Using MSR-deficient mice, we successfully raised a novel monoclonal antibody against human MSR together with high-titer antisera. These antibodies specifically recognized human tissue macrophages and human MSR protein purified from differentiated THP1 cells. In normal brain, MSR staining was mainly distributed to the perivascular cells, which correspond to Mato's fluorescent granular perithelial cells (Mato cells). In the lesions of ischemia and Alzheimer's disease, a subset of microglia stained positive for MSR. These novel antibodies are useful tools for analysis of MSR expression in human tissues.  相似文献   
89.
PURPOSE: Electron beam tomography (EBT) permits acquisition of images with high spatial and temporal resolution. The value of EBT and other imaging modalities for the depiction of patent coronary artery bypass grafts (ACVB, IMA) are compared to coronary angiography and an overview of current results is given. MATERIAL AND METHODS: Graft patency can be evaluated with indirect methods stress, such as echocardiography, radionuclide ventriculography, myocardial scintigraphy, positron-emission tomography (PET) and direct imaging modalities, such as Doppler/2D echocardiography, EBT, spiral computed tomography (SCT) and magnetic resonance angiography (MRA). RESULTS: With indirect methods graft patency can be evaluated with sensitivity of 64-100% and specificity of 73-100%. EBT and SCT are equivalent in sensitivity (= 94%) in the assessment of open venous grafts and specificity is up to 100%, but EBT is superior in the diagnosis of patent IMA grafts (sensitivity 100% vs 89%). Visualization of high-grade venous bypass stenosis seems possible with EBT. MRA with gradient echo technique is highly accurate in the assessment of patent venous grafts (sensitivity 77-93%) but has limited value in the evaluation of IMAs (sensitivity = 53%). Promising are ultrafast 3D-MRA methods which permit high accuracy (sensitivity = 94-96%) in assessing venous and arterial grafts. DISCUSSION: Indirect imaging methods cannot differentiate between an occluded bypass, progression of coronary artery disease and myocardial infarction. EBT and SCT are equivalent in the diagnosis of open and occluded venous grafts, but EBT is superior in the assessment of patent IMA grafts. Visualization of high-grade venous bypass stenosis seems possible with EBT. MRA techniques, especially ultrafast 3D-MR methods, are highly accurate in the assessment of patent venous and arterial grafts but are still limited to scientific research.  相似文献   
90.
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