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71.
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The study of the complement-outer bacterial membrane interactions is gaining enthusiasm for applying a continuous development of more specialized techniques. In this paper a novel flow cytometry technique shows that highly fluorescent lucifer yellow-stained Neisseriae gonorrhoeae when exposed to the redox reaction of p-nitro blue chloride tetrazolium (NBT), as formazan precipitation takes place, a shift to lesser fluorescent channels of the histogram population occurs. That effect is labeled NBT-laser beam quenching (NBT-LBQ). A significant difference by Kolmogorov-Smirnov summation curve analysis is found between complement heat-inactivated and its counterpart assessed with normal complement microorganisms. The operation of this NBT-LBQ effect by microbial flow cytometry casts an interesting potential for the evaluation of the outer membrane-complement-interaction of serum sensitive microorganisms.  相似文献   
73.
Product update     
OBJECTIVE: To compare fluoroscopic freeze-frame digital images with conventional 105-mm spot films during voiding cystourethrography (VCUG) with regard to diagnostic quality and radiation dose. MATERIALS AND METHODS: VCUG was performed on 57 consecutive children by a commercially available fluoroscopic digital system. Both freeze-frame digital images and conventional 105-mm spot films were obtained during 90 s of fluoroscopy. Skin radiation dose was assessed separately for spot films and for both fluoroscopy and spot films, employing thermoluminescent crystals on the anterior surface of the body. Patients were classified into three age groups: group A younger than 12 months, group B 1-5 years old and group C 5-12 years of age. RESULTS: Digital and conventional images provided diagnostically identical results in 108 out of 114 ureters examined (94.7%). Percentage reductions in skin radiation dose due to the fluoroscopic hard copies compared with the four 105-mm radiographs were 53.8%, 50.5% and 57.1% for groups A, B and C, respectively. CONCLUSION: Substitution of conventional 105-mm spot films during VCUG with digital fluoroscopic hard copies resulted in a substantial reduction in radiation dose. Digital images were as accurate as the conventional films in excluding vesicoureteric reflux (VUR). The two methods correlated well in diagnosing and grading VUR.  相似文献   
74.
Callahan  D. Pedigo  B. 《Software, IEEE》2002,19(5):57-62
Academia and industry disagree about what students should learn in school versus on the job. When the University of Alabama at Birmingham developed a graduate program in electrical and computer engineering, they consulted industry executives to develop a curriculum that addresses industry's needs without compromising academic fundamentals.  相似文献   
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The first 96 and 192 beam vacuum Hohlraum target experiments have been fielded at the National Ignition Facility demonstrating radiation temperatures up to 340 eV and fluxes of 20 TW/sr as viewed by DANTE representing an ~20?times flux increase over NOVA/Omega scale Hohlraums. The vacuum Hohlraums were irradiated with 2 ns square laser pulses with energies between 150 and 635 kJ. They produced nearly Planckian spectra with about 30±10% more flux than predicted by the preshot radiation hydrodynamic simulations. To validate these results, careful verification of all component calibrations, cable deconvolution, and software analysis routines has been conducted. In addition, a half Hohlraum experiment was conducted using a single 2 ns long axial quad with an irradiance of ~2×10(15)?W/cm(2) for comparison with NIF Early Light experiments completed in 2004. We have also completed a conversion efficiency test using a 128-beam nearly uniformly illuminated gold sphere with intensities kept low (at 1×10(14)?W/cm(2) over 5 ns) to avoid sensitivity to modeling uncertainties for nonlocal heat conduction and nonlinear absorption mechanisms, to compare with similar intensity, 3 ns OMEGA sphere results. The 2004 and 2009 NIF half-Hohlraums agreed to 10% in flux, but more importantly, the 2006 OMEGA Au Sphere, the 2009 NIF Au sphere, and the calculated Au conversion efficiency agree to ±5% in flux, which is estimated to be the absolute calibration accuracy of the DANTEs. Hence we conclude that the 30±10% higher than expected radiation fluxes from the 96 and 192 beam vacuum Hohlraums are attributable to differences in physics of the larger Hohlraums.  相似文献   
78.
Over the past quarter century, much effort has been devoted to the design and development of simulation modeling languages, and to methods for the development of simulation models themselves. Less effort, however, has been expended on the design of the experimental models upon which simulation studies are based. This paper describes a methodology for the determination of near optimal solutions considering experimental design and simulation modeling. Using this methodology, simulation scenarios are created and analyzed using an analysis of variance (ANOVA)-based experimental design. This paper also presents an application of this method in analyzing a manufacturing system design problem.  相似文献   
79.
“Row nucleated lamellar” structures are formed when highly crystalline polymers are melt-extruded and recrystallized under high stress. Polyethylene (PE) and polypropylene (PP) films with row lamellar structures have been utilized to produce microporous membranes. Birefringence measurements of melt-extruded PE films show that improved film orientation can be achieved by annealing, extruding at higher speed, and using higher molecular weight polymers. Images from scanning tunneling, atomic force, and field emission scanning electron microscopy (STM, AFM, and FESEM) clearly show the lamellar structures in the melt-extruded PE and PP films. Microscopy results also show that surface lamellar textures are more pronounced with thicker lamellae and are better aligned along the extrusion direction after annealing. X-ray diffraction results show that the increase in film orientation can be attributed to increased lamellar perfection and orientation during annealing and also to better crystallite alignment along the machine direction with higher extrusion speed or with higher molecular weight. High-resolution capabilities of STM, AFM, and FESEM prove to be very effective tools in elucidating lamellar structures in polymeric membrane precursors and can be used as an aid in establishing structure–process–property relationships in making microporous membranes. © 1994 John Wiley & Sons, Inc.  相似文献   
80.
An outbreak of a febrile illness characterized by headache, ocular pain, myalgia, and arthralgia occurred during June 1994 among Peruvian army troops in Northern Peru. On June 14-16, 1994, clinical data and blood samples were obtained from eight soldiers with a febrile illness, and from 26 others who had a history of febrile illness during the past three months. A follow-up blood sample was obtained 107 days later from four of the febrile and seven of the afebrile soldiers. Serum samples were tested for dengue (DEN), Oropouche (ORO), and Venezuelan equine encephalitis (VEE) IgM and IgG antibodies by an enzyme-linked immunosorbent assay (ELISA). Virus isolation was performed by inoculation of newborn mice and Vero cell cultures. Viral isolates were identified by immunofluorescence, ELISA, and nucleotide sequencing. A VEE virus infection was confirmed in three of the eight febrile soldiers, two by virus isolation, and one by serology. Antigenic analysis indicated that one of the virus isolates was similar to VEE subtype I, variety ID, viruses previously isolated in Colombia and Venezuela. Nucleotide sequence data showed that both viral isolates were identical to one another and closely related to VEE ID viruses previously isolated in Peru, Colombia, and Venezuela. Serologic results showed that two of 26 afebrile soldiers had IgM antibody to VEE and four had IgG antibody to VEE; two febrile soldiers had IgG antibody in their first serum samples. Oropouche-specific IgM antibody was detected in one of the eight febrile and five of the afebrile soldiers, and 18 of the 34 soldiers had low titers of ORO IgG antibody titers, which did not meet the diagnostic criteria for confirmed cases. All soldiers were negative for DEN IgM antibody, and 10 had flavivirus IgG antibody that reacted with DEN antigens. These data indicated that VEE ID virus was one of the causes of illness among Peruvians soldiers and that this was the first association of this VEE subtype with human disease in Peru.  相似文献   
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