Log of Observations-Phase One
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01/17/01(Updated by Jenn)-Today we attempted using different concentrations. We used the the antibiotic that worked the best and also the worst for each bacteria. For Staph. aureus, the best was Vancomycin and the worst was Oxacillin. For Staph. Epidermidis, the best was Oxacillin and the worst was Vancomycin. For the best ones, we halved the amount of antibiotic, and for the worst, we doubled it. This means we used 200mg/2ml of water and 50mg/2ml of water for both antibiotics. We are optimistic about our results which we will observe tomorrow. 01/18/01(Updated by Emily)-Today we checked the results of yesterday's disk innoculations and discovered many new results. We found that the doubled amount of Oxacillin in Staph Aureus increased the zone of inhibition by .2 millimeters. Our result for Vancomycin with Staph Aureus, however, was quite unexpected. Instead of decreasing the zone of inhibition, the decreased amount of the antibiotic seemed to increase the zone. In this case, the zone was increased by .6 millimeters. At this point in our research, we are not sure as to why this occurred. The results for the Staph Epidermidis bacteria was more regular than those of the Aureus bacteria. In the case of Staph Epidermidis, we cut the amount of oxacillin in half. Due to this, we noted a decrease in the zone of inhibition by 1.6 millimeters, which was almost a direct half from the original concentration. The doubled amount of Vancomycin led to a 2 millimeter increase in the zone of inhibition of this bacteria. Due to the results of this experiment,(with the exception of the odd Staph Aureus reading)we have been able to determine that the amount of concentration of the antibiotics does have a direct effect upon the size of their zone of inhibition. 
01/31/01(Updated by Jenn)-We are getting ready to get into the next stage of our project. We are doing much research on rats and their anatomy. Fortunatley, we have had some luck with finding these things. This is going to take a lot of preparation before beginning the actual lab part of this. We are getting things ready, and are quite excited. 02/13/01(Updated by Jenn)-We are getting things ordered, and will start as soon as we have what we need. We will probably have the rats first, and that will give us a chance to make some initial observations before we do anything to them.
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