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The aim of this study was to compare the sensitivities of commercial monoclonal antibody pools to be used as an initial rapid screen for detection of viral antigens in respiratory secretions. The availability of commercial monoclonal antibodies has dramatically improved the detection of viruses by immunofluorescence techniques in exfoliated cells obtained from respiratory secretions. Several companies have recently introduced monoclonal antibody pools to detect the presence of respiratory viruses in a single preparation. Ninety-four stored slide preparations that had previously been examined by individual monoclonal antibodies were tested using three commercial monoclonal antibody pools produced by Sanofi (UK), Dako (UK), and Quadratech (UK). These monoclonal antibody pools had a sensitivity of 79.6%, 90.9%, and 100%, respectively, when compared with the original results. The overall intensity of immunofluorescence was also examined.  相似文献   
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The draft Long-Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) contains Cryptosporidium log-inactivation CT tables (ozone-in-water concentration [residual], “C” times contact time, T). Depending on water temperature, Cryptosporidium CT values that are listed are 15 to 25 times greater than CT values for equivalent Giardia log-inactivation credit. The elevated operating dose required for Cryptosporidium log-inactivation credit has the potential to increase disinfection by-product (DBP) formation (e.g., bromate). Calculating CT value accurately will minimize ozone dose, which will decrease operating cost and lower DBP formation, and at the same time maintain disinfection protection through implementation of scientifically based safety factors. Various methods are available for calculating CT value. The method chosen depends largely on the available information concerning ozone residual characteristics and hydrodynamic features of the ozone contactor, plus local regulatory requirements. Four methods are discussed in this paper. Each method can be used to calculate Giardia, virus, and Cryptosporidium log-inactivation credit.  相似文献   
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Nanostructured polymer blends prepared via anionic ring opening polymerizations of cyclic monomers in the presence of a pre-made polymer melt exhibit a number of special properties over traditional polymer blends and homopolymers. Here, we report on a simple and versatile method of in situ polymerization of macrocyclic carbonates in the presence of a maleic anhydride polypropylene (mPP) matrix and a surface-active compatibilizer (i.e. PC grafted onto a mPP backbone generated in situ) to yield a micro- and nanostructured polymer blends consisting of a polycarbonate (PC) minor phase, and a polypropylene (PP) major phase. By varying the processing conditions and concentration of the macrocyclic carbonate it was possible to reduce the size of the PC dispersions to an average minor diameter of 150 nm. NMR and TEM characterizations indicate that the PC dispersions do not influence crystal content in the PP phase. Overall, the results point to a simple strategy and versatile route to new polymeric materials with enhanced benefits.  相似文献   
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A value-based test is presented for economic screening of electric utility demand-side management (DSM) programs. The widely used least cost test is valid if the programs do not alter the amount or value of energy services provided to customers. But, in general, DSM programs have such effects and, as a result, the value consumers receive is changed. A more general economic efficiency test, the most value test, provides a practical method for considering the effects of DSM on customer value. The version presented allows for multiple load periods and can account for rate impacts on several customer classes. Four typical DSM programs are evaluated as illustrations  相似文献   
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OBJECTIVES: 1) To quantify the frequency of underrecognized Neisseria gonorrhoeae and Chlamydia trachomatis cervical infections in women tested in the ED, 2) to describe and compare the characteristics of those treated and not treated during the initial visit, and 3) to quantify the delay interval until treatment was provided. METHODS: A 2-year, retrospective consecutive case series was performed from June 1, 1992, to May 31, 1994. There were 148 women with > or = 1 discrete occurrence of culture-proven cervical N. gonorrhoeae or C. trachomatis infection studied. All the patients were evaluated in a university-affiliated, tertiary care hospital-based ED with a large rural referral area. The main outcome measures were the proportions of patients with positive cultures both treated and not treated in the ED, the clinical characteristics of each group, and the proportion remaining untreated or experiencing treatment delays of > 2 weeks after attempted phone, mail, and public health follow-up. RESULTS: Of 157 occurrences of positive cultures for N. gonorrhoeae or C. trachomatis, 86 (53%) were treated with a regimen suggested by the CDC prior to ED release. The proportion of women with isolated C. trachomatis infections that were underrecognized and untreated initially was larger than the proportions with isolated N. gonorrhoeae or combined infections (79% vs 27% and 53%, respectively, p < 0.0001). Women with findings suggestive of advanced disease (history of fever or chills, or examination evidence of temperature > 38 degrees C, purulent vaginal discharge, or any uterine/salpinx/ovarian tenderness) were more often recognized and treated with appropriate antibiotics initially (p = 0.02 to < 0.00001 for all). After phone, mail, and public health follow-up, treatment could not be documented for 25% of the occurrences, in all cases due to an inability to locate the patient. An additional 20% of the women did not receive treatment for 14-60 days. CONCLUSIONS: In this population, both N. gonorrhoeae and C. trachomatis cervical infections are frequently underrecognized in the ED, with isolated C. trachomatis infections associated with significantly higher proportions of underrecognition. Many affected women remain untreated for extended intervals, creating public and individual health risks. Improved point of contact detection, follow-up, and treatment policies are needed to limit these risks.  相似文献   
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High speed power     
This paper presents the need for compatibility between European rail networks. This leads to the adoption of dual 25 kV as the power of choice for operators. Dual 25 kV literally doubles the power available to rail networks, helping rail operators to meet some of the demands they are facing. Not surprisingly, this fact, along with the EU directive on 'interoperability of the trans-European high speed rail system', which aims to ease the circulation of high-speed trains through the various train networks of the European Union, will lead it to become the future standard across Europe  相似文献   
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Presents remarks from the president of the APA's Division 13 (Division of Consulting Psychology). The author discusses the second annual Colorado conference on consulting to corporations and business; the planning for Division activities at the APA convention in Los Angeles; and the affect of health reform on consulting psychology and consulting psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Adaptive fuzzy c-shells clustering and detection ofellipses   总被引:6,自引:0,他引:6  
Several generalizations of the fuzzy c-shells (FCS) algorithm are presented for characterizing and detecting clusters that are hyperellipsoidal shells. An earlier generalization, the adaptive fuzzy c-shells (AFCS) algorithm, is examined in detail and is found to have global convergence problems when the shapes to be detected are partial. New formulations are considered wherein the norm inducing matrix in the distance metric is unconstrained in contrast to the AFCS algorithm. The resulting algorithm, called the AFCS-U algorithm, performs better for partial shapes. Another formulation based on the second-order quadrics equation is considered. These algorithms can detect ellipses and circles in 2D data. They are compared with the Hough transform (HT)-based methods for ellipse detection. Existing HT-based methods for ellipse detection are evaluated, and a multistage method incorporating the good features of all the methods is used for comparison. Numerical examples of real image data show that the AFCS algorithm requires less memory than the HT-based methods, and it is at least an order of magnitude faster than the HT approach.  相似文献   
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