Property of Yulia-i'm very thankful to you to provide the easier explaination.it's true that many undergrad students have problem in dilution.and the worst thing is if the lecturers/tutors assume that the students are familiar with the concept. It is true that they have learned it in high school, but most of the time they will forget.regarding the example 2 given, you dilute a sample (10 ml the final volume) 10x10x10=10 to the power of 3. And u inoculate 0.1 ml in your medium.so supposed the final volume of your medium is 1ml right?
AbstractIn a systematic approach, 37 duplicate samples of open system circuits (Bennett MA-1 ventilators) of patients in medical and surgical intensive care units were processed by direct and serial (APHA guidelines) dilutions. The paired difference test on 15 of the in-use circuitry solution samples indicated no difference between the direct and serial dilution methods (P less than 0.001). Seventy-seven additional respiratory therapy circuitry samples from similar intensive care patients were analyzed via a direct dilution method alone and processed microbiologically. The direct dilution procedure was a rapid and accurate means of evaluation of microbial contamination in the range of greater than or equal to 10 to less than or equal to 10(6) CFU/ml. High densities of organisms frequently were found. Sites of contamination included the proximal or patient end of the circuitry (heaviest), the nebulizer trap, and the distal or humidifier portions of the circuitry. The contaminants found were predominantly gram-negative nonfermenters: Acinetobacter calcoaceticus var.
Antitratus, Pseudomonas aeruginosa, Pseudomonas maltophilia, and Flavobacterium meningosepticum. Fermenters were Klebsiella pneumoniae, Proteus sp., Enterobacter cloacae, Citrobacter diversus, and Enterobacter agglomerans.
Infrequently, gram-positive Streptococcus spp. And Staphylococcus spp. Full text Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the (1.0M), or click on a page image below to browse page by page.
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4 Fold Serial Dilution
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Advantages And Disadvantages Of Serial Dilution Chemistry
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