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1.
Human papillomavirus (HPV) types 16 and 18 in 66 women with histologically documented lesions of the genital tract and 64 control cohorts were investigated. The efficacies of in situ hybridization and polymerase chain reaction (PCR) in detecting HPV 16 and 18 DNA were analyzed. In order to assess the usefulness of replacing biopsies with cervical scrapes, the two samples were compared by PCR. The prevalence rates of HPV infection by PCR were 59.1 and 10.9% in patients and controls, respectively. PCR was three times more sensitive than in situ hybridization (52.6 versus 17.8%). However, the need to improve PCR sensitivity by subsequent dot blot hybridization reduced one of the main advantages of PCR, i.e., expeditious diagnosis. Cervical scrapes were less sensitive than biopsies (13.6 versus 53%), although with four (6.1%) patients with intraepithelial neoplasias, HPV DNA was identified only by means of cervical scraping. We conclude that obtaining biopsy specimens and cervical scraping are complementary sampling procedures.  相似文献   
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In this paper, a novel three-dimensional (3-D) space-vector algorithm for four-leg multilevel converters is presented. It can be applied to active power filters or neutral-current compensator applications for mitigating harmonics and zero-sequence components using abc coordinates (referred from now on this paper as natural coordinates). This technique greatly simplifies the selection of the 3-D region where a given voltage vector is supposed to be found. Compared to a three-level modulation algorithm for three-leg multilevel converters, this algorithm does not increase its complexity and the calculations of the active vectors with the corresponding switching time that generate the reference voltage vector. In addition, the low-computational cost of the proposed algorithm is always the same and it is independent of the number of levels of the converter.  相似文献   
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Monitoring and analysis of the energy cost of an MBR   总被引:2,自引:0,他引:2  
Certain regions in the south of Europe are suffering an acute lack of water. One way to solve this hydric deficit is to use membrane bioreactors (MBR) to reuse the treated wastewater in tasks where drinking water is not required, e.g. irrigation. The aim of this research was to monitor physical-chemical (COD, BOD, and TN) and microbiological (EF, TC, and FC) parameters, as well as the energy costs in a Kubota MBR pilot plant located in Southeast Spain for one year, as well as to check the feasibility of the MBR process. The system showed a high robustness providing a fairly constant effluent with a large reduction of the entry pollutants and thus providing a highly reliable operation. High TSS, COD, BOD, NH+4 and TN removal efficiencies up to 97, 94, 95, 98 and 81% respectively where achieved. The removal of the different microbials was quite high, with values in the permeate below 10 colony forming units (CFUs) most of the time. Some problems like blackouts, high temperatures and cleaning processes altered the normal operation lowering the retention of the different compounds and microorganisms. Regarding the energy consumption, two fluxes, 19 and 25 LMH were tested. Assuming a price for the electric supply of 0.0806 €/kW, the prices of the treated water for the two fluxes were 0.49 and 0.39 €/m3 and the total consumptions were 6.06 and 4.88 kWh/m3 for 19 and 25 LMH respectively. Aeration comprised almost 50% of the total energy requirements.  相似文献   
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Three commercial nanofiltration (NF) membranes, models NF 270, NF 90 (Dow Chemical Inc.) and Desal-HL-51 (GE Water), have been used to investigate trihalomethane and haloacetic acid formation potential (THMFP and HAAFP); the influence of conductivity on permeate flow-rate was also studied. Natural waters from two different sources in Alicante province (SE Spain) were analyzed.At the end of the NF experiments on water from the Amadorio reservoir, the Desal-HL-51, NF 270 and NF 90 membranes exhibited a 20, 25 and 45% drop in permeate flow-rate, respectively. The drop in flow-rate increased with conductivity for all of the membranes, as it becomes evident when comparing the experiments at conductivities of 700 and 6000 µS/cm.Over 90% of the formation potential of bromodichloro methane and dibromochloro methane was eliminated using the NF 90 membrane. The NF 270 and Desal-HL-51 membranes produced smaller decreases in THMFP. Among the haloacetic acids, dichloroacetic acid was least reduced, by 60% and 30% for waters from the Amadorio and Pedrera reservoirs, respectively. The analytes differed considerably.  相似文献   
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Pendred's syndrome is manifested by congenital sensorineural deafness in association with familial goiter due to defective organic binding of iodine in the thyroid gland. The majority of patients with Pendred's syndrome are euthyroid. We report on an unusual case of a patient with Pendred's syndrome presenting with amenorrhea and late-onset hypothyroidism.  相似文献   
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This work presents the fabrication of 3D‐printed composite objects based on copper(II) 1D coordination polymer ( CP1 ) decorated with thymine along its chains with potential utility as an environmental humidity sensor and as a water sensor in organic solvents. This new composite object has a remarkable sensitivity, ranging from 0.3% to 4% of water in organic solvents. The sensing capacity is related to the structural transformation due to the loss of water molecules that CP1 undergoes with temperature or by solvent molecules' competition, which induces significant change in color simultaneously. The CP1 and 3D printed materials are stable in air over 1 year and also at biological pHs (5–7), therefore suggesting potential applications as robust colorimetric sensors. These results open the door to generate a family of new 3D printed materials based on the integration of multifunctional coordination polymers with organic polymers.  相似文献   
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