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51.
9%Cr steels have been in use in power generation for over 20 years. Over this time, there have been a number of incidents of failure by Type IV cracking at welds initiating sub-surface, making surface inspection procedures unsuitable for crack detection. Replication to identify creep cavitation damage can potentially give an early warning of imminent cracking, but has proved unsuccessful in high Cr martensitic steels. Electromagnetic (EM) inspection can provide fast inspection of welded components with minimal surface preparation and some increase in inspection depth. This paper shows the results of accelerated creep tests carried out on a P91 pressure vessel, with EM inspections during regular test interruptions. The results show that EM inspection gave indications of damage in the latter stages of creep cavitation. EM is considered to have the potential for quick assessment of component through thickness damage, flagging up locations of potential problems for more detailed investigation.  相似文献   
52.
E-Health systems, through their use of Internet and wireless technologies, offer the possibility of near real-time data integration to support the delivery and management of health care. In practice, the wide range of choice in technologies, vendors, protocols, formats, and information representations can make even simple exchanges of information between systems problematic. Much of the focus on healthcare interoperability has been on resolving interoperability issues of system to system information exchanges. But issues around people to people interactions and people to system interactions are just as important to address from an interoperability point of view. In this paper, we identify interoperability deficiencies in collaborative care delivery and develop a methodology in two parts. In the first part, an ontology is developed to represent collaborative care delivery. In the second part, the ontology is used to design an architecture for interoperable clinical information system design. We then use a case study in palliative care to provide a proof of concept of the methodology. The case study provides an inventory of the interoperability requirements for palliative care and a perspective on the design and implementation of a people oriented clinical information system that supports collaborative health care delivery in palliative care.  相似文献   
53.
Over the last 10 years there has been continuous innovation and evolution in the technology of web applications. While originally designed as a telecom testing platform, TTCN-3 has proven to be a flexible and powerful platform for web application testing throughout this period. Major challenges to testing have been integration with unit test frameworks, service-oriented architecture, rich client interfaces, and security vulnerabilities. Through careful analysis and practical experience in industrial projects we have developed mechanisms to address each of these aspects of web application testing in TCN-3. These mechanisms are summarized here with examples drawn from our industrial experience to show how TTCN-3 provides significant advantages for testing web applications in comparison to other tools typically used in industry. We also present a significant extension to the model architecture for TTCN-3 which greatly facilitates web application testing that has been implemented by a major vendor and is now under consideration by the ETSI standards committee.  相似文献   
54.
ABSTRACT

The objective of this study is to determine the occurrence and level of aflatoxins (AFs) contamination in freshly harvested maize for human consumption in rural Kenya. Maize kernels and freshly milled maize flour (n = 338) were collected from households in Siaya and Makueni counties. While both counties are representatives of different environmental and climate conditions, Makueni County is the area with reported outbreaks of aflatoxicosis. Samples were analysed for AFB1, AFB2, AFG1, and AFG2 using Ultra High-Pressure Liquid Chromatography with Fluorescence detection. AFs were detected in 100% of the samples with the range of 2.14–411 µg/kg. The geometric mean of total AFs in all samples from Makueni County is 62.5 μg/kg with 95% CI: 53.7, 71.4 while in Siaya County is 52.8 μg/kg with 95% CI: 44.0, 61.7. This study showed that AFs contamination is prevalent in maize-based foods in the region.  相似文献   
55.
56.
Oie CS  Albaugh CE  Peyton BM 《Water research》2007,41(6):1235-1242
Alkaliphiles and halophiles have considerable potential to treat organic pollutants in industrial wastewaters having high pH and salinity. As model aromatic compounds, benzoate and salicylate at concentrations up to 380 mg/L were degraded as carbon and energy sources by Halomonas campisalis, an alkaliphile and moderate halophile. Aerobic batch experiments were performed at 50 and 100g/L NaCl and pH 9. Detected metabolites, catechol and cis, cis-muconate, indicated that H. campisalis used the ortho degradation pathway for both substrates. For benzoate concentrations up to 1600 mg/L, the intermediate 2-hydroxymuconic semialdehyde (2HMSA), characteristic of the meta pathway, was not detected. Improved understanding and characterization of these degradation processes in high pH, high salt systems may lead to improved application of haloalkaliphiles for industrial wastewater treatment.  相似文献   
57.
Textured alumina has been fabricated previously by either hot-deformation processing, to produce moderate texture, or templating with aligned platelets, to produce stronger texture. Fracture-toughness measurements on ceramics fabricated by hot deformation have indicated only a modest improvement in toughness compared with that of untextured ceramics, while measurements on more strongly textured ceramics have been very limited. In this work, a simplified process for fabricating highly textured alumina was developed, using a solvent-based slurry, tape casting, and liquid-phase sintering. Grain size was tailored to maximize the likelihood of grain bridging and crack deflection. Image analysis was used to characterize morphologic texture, and X-ray pole-figure analysis was used to measure crystallographic texture. Fracture tests revealed significant changes to the crack path as a result of the texture. However, the apparent fracture resistances measured using single-edge notched-beam samples were similar for textured and untextured ceramics. The lack of apparent toughening resulting from texturing is discussed in light of previous results.  相似文献   
58.
59.
Hormonal stimulation of Gq-protein coupled receptors triggers Ca2+ mobilization from internal stores. This is followed by a Ca2+ entry through the plasma membrane. Drosophila Trp and Trpl proteins have been implicated in Ca2+ entry and three mammalian homologues of Drosophila Trp/Trpl, hTrp1, hTrp3 and bTrp4 (also bCCE) have been cloned and expressed. Using mouse brain RNA as template, we report here the polymerase chain reaction-based cloning and functional expression of a novel Trp, mTrp6. The cDNA encodes a protein of 930 amino acids, the sequence of which is 36.8, 36.3, 43.1, 38.6, and 74. 1% identical to Drosophila Trp and Trpl, bovine Trp4, and human Trp1 and Trp3, respectively. Transient expression of mTrp6 in COS.M6 cells by transfection of the full-length mTrp6 cDNA increases Ca2+ entry induced by stimulation of co-transfected M5 muscarinic acetylcholine receptor with carbachol (CCh), as seen by dual wavelength fura 2 fluorescence ratio measurements. The mTrp6-mediated increase in Ca2+ entry activity was blocked by SKF-96365 and La3+. Ca2+ entry activity induced by thapsigargin was similar in COS cells transfected with or without the mTrp6 cDNA. The thapsigargin-stimulated Ca2+ entry could not be further stimulated by CCh in control cells but was markedly increased in mTrp6-transfected cells. Records of whole cell transmembrane currents developed in response to voltage ramps from -80 to +40 mV in control HEK cells and HEK cells stably expressing mTrp6 revealed the presence of a muscarinic receptor responsive non-selective cation conductance in Trp6 cells that was absent in control cells. Our data support the hypothesis that mTrp6 encodes an ion channel subunit that mediates Ca2+ entry stimulated by a G-protein coupled receptor, but not Ca2+ entry stimulated by intracellular Ca2+ store depletion.  相似文献   
60.
This study compared the performances of three human papillomavirus (HPV) detection tests with specimens collected by three alternative procedures. The HPV tests included the Hybrid Capture Tube test (HCT), the microplate-based Hybrid Capture II test (HC II), and the MY09-MY11 L1 consensus primer PCR-based assay. Initial cervical specimens were collected from study subjects with a broom device, and after Papanicolaou smears were made, residual specimens were placed into PreservCyt (PC), a liquid cytology medium. A second specimen was collected from each subject and placed into Digene Specimen Transport Medium (STM). The device for collection of the second specimen alternated with consecutive subjects between a conical cytology brush and a Dacron swab. At the 1.0-pg/ml cutoff, the results of the HC II agreed well with those of the PCR. Specifically, when PCR data were restricted to the types found by the HC II (HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68), there was greater than 90% agreement between the HC II and PCR results with both STM and PC. At a lower cutoff (0.2 pg/ml), HC II-positive results increased further, especially when the test was applied to the PC specimens. However, false-positive HC II results were more often observed at the 0.2-pg/ml cutoff. HC II yielded the highest HPV positivity with specimens placed into PC, followed by specimens collected with a conical brush and placed into STM and, last, by those collected with a Dacron swab and placed into STM. Our results demonstrate the utility of both the STM and PC specimen collection methods and show good agreement between the HC II and PCR.  相似文献   
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