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71.
Two membrane bioreactors were operated with biological phosphorus removal, carbon degradation and denitrification to check how comparable and representative they were compared to full-scale plants. One was fed with synthetic municipal wastewater and was switched from pre- to post-denitrification without carbon dosing. The influent of the second plant was drawn from a separate sewer. This plant worked the whole time with post-denitrification without carbon dosing. The synthetic wastewater was designed to achieve a realistic COD:TN:TP ratio and tested for long time biodegradability. The eliminations were >94% (COD) and >97% (TP) for both plants. This was within the range of commercial plants, as well as the TN elimination for the pre-denitrification of plant I (>75%). The eliminations of TN for post-denitrification were above 80% for both plants despite the high influent concentrations and the missing carbon source for post-DN. A calculation of the nitrification rates gave values similar to those found in literature (1-6 mgN/(gMLVSSh)). A comparison of the denitrification showed expected rates for pre-denitrification (7.5 mgN/(gMLVSSh)) for plant I. The values (on average 1.8 mgN/(gMLVSSh)) for post-denitrification in plant II were higher than endogenous denitrification rates which are commonly reported as 0.2-0.8 mgN/(gMLVSSh). The rates for post-denitrification in plant I were only slightly higher than endogenous ones (0.9 mgN/(gMLVSSh)).  相似文献   
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Patients infected with HIV have become a steadily increasing part of most medical practices. Because most patients with HIV-related problems have manifestations in the head and neck, it is important that these be understood and recognized. This article briefly reviews the various otolaryngologic manifestations of HIV infection, including otologic, nasal, and paranasal sinus; oral cavity, pharynx, and larynx; and the neck.  相似文献   
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A method for determining the extents of a qualified viewing space (QVS) based on repeatable and reproducible luminance measurements of augmented and virtual reality near‐eye displays is described. This QVS mapping can also use other display performance metrics such as (1) Michelson contrast, (2) modulation transfer function, or (3) color as boundary condition parameters. We describe the use of a 4‐mm‐diameter entrance pupil, 1° to 2° field of view tele‐spectroradiometer, to determine the luminance and color uniformity of the virtual image. A 1‐mm‐diameter entrance pupil is used to map the QVS boundaries based on luminance at the center of the virtual image. The luminance measurement results from a pair of binocular augmented reality display glasses in three separate eye relief planes of the QVS of both eyes are presented. The data are further reduced to provide a perimeter profile of the QVS for the 50% of peak luminance boundary points in each eye relief plane.  相似文献   
74.
The enzymology and clinical manifestations of total parenteral nutrition (TPN)-induced liver abnormalities have been investigated extensively. The cause, pathogenesis, and treatment of TPN-related hepatic and biliary dysfunction in adults still are not well understood, however. The findings of experimental studies in animals has not necessarily correlated with the human data, and there have been few prospective, randomized controlled trials examining the mechanism, cause, or treatment of TPN-induced hepatobiliary toxicity in adults. This article examines the animal models of pathogenesis and treatment of TPN-induced intrahepatic and extrahepatic abnormalities, and provides a discussion of abnormalities seen in humans.  相似文献   
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Within 3 hours, 10 healthy male volunteers were infused 500 ml of a 5 percent emulsion in which 25 percent of the fat proportion had been replaced by MCT-fats. As expected, the ketone body concentration in the blood rose, while pyruvate remained constant and lactate dropped. The results show that, basically, a MCT-containing fat infusion is suited for parenteral nutrition and, because of their specific properties, medium chain triglycerides may be used as rapid energy donators.  相似文献   
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