Molecular techniques offer improvements over immuno-logical methods in both specificity and sensitivity. Techniques include ribotyping, pulsed-field gel electro-phoresis (PFGE), analysis of repetitive elements, or DNA sequence determination of individual loci. These techniques are particularly useful in detecting ''microevolution'' of rapidly evolving genes among related meningococci and for understanding their short-term epidemiology. For example, DNA sequence-based analysis of porB gene polymorphisms has led to improvements in the discrimination between immunologically similar meningococci and in defining the relationships among them.
For longer-term analysis of meningococcal epidemiology and population structure, ''multilocus'' characterization techniques are more useful. These techniques index neutral, slowly evolving variation at widely distributed genetic loci around the meningococcal chromosome, such as those encoding cytoplasmic ''housekeeping'' enzymes involved in central metabolic processes. As such, these methods are more representative of the genomic sequence
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The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.