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Bridgewater College, Mark Thompson (photographer), Basketball action photograph of Terry Cox, 22, shooting a 3 pointer, undated
No full textArchival photograph from Bridgewater College Special Collectionshttps://digitalcommons.bridgewater.edu/c_last_name_individuals_photos/1007/thumbnail.jp
Prevalence rates of tetB, tetA, and tetM tetracycline resistance genes in environmental Escherichia coli isolates from local waterways
Get PDFThe purpose of this study was to determine the prevalence rates of the tetracycline resistance genes tetA, tetB, and tetM in environmental Escherichia coli isolates. Samples were from both an urban and an agricultural waterway were filtered and incubated with Coliscan™ medium to differentiate for fecal coliforms. The resulting colonies were streaked onto EMB and then TSA plates to ensure isolation and presence of E. coli. All media used were supplemented with 10 µg/mL tetracycline in order to maintain selective pressure on the isolates. DNA from the isolates was then extracted and PCR was run using tetA, tetB, and tetM primers to see what genes were present in each isolate, using conditions from a published study. Because multiple non-specific products were observed, we modified the procedure by increasing the annealing temperature from 54°C to 56°C, shortening cycling times, and lowering the concentration of Mg+2. These changes greatly improved specificity with the tetA and tetB, but not the tetM primers. Overall, results tentatively suggested that tetA occurred in isolates from urban and agricultural areas at prevalence rates of 100% and 33.3%, respectively and possibly in a lab strain of E. coli, K12. Results with tetM were too difficult to interpret due to non-specific product formation, but tetB was possibly present in at least one of the environmental strains and in E. coli K12
Bridgewater College, Photograph of President Warren D. Bowman smiling behind a pulpit, undated
No full textArchival photograph from Bridgewater College Special Collectionshttps://digitalcommons.bridgewater.edu/b_last_name_individuals_photos/1005/thumbnail.jp
Signal and Noise Analysis in an Undergraduate Instrumental Analysis Laboratory
Get PDFUnderstanding the difference between signal and noise in a measurement is fundamental to analytical chemists. The typical instruments found in an undergraduate chemistry department can be used to teach this concept, as well as signal averaging, by giving students hands-on experience with measurements and data processing. This work presents an undergraduate laboratory module (homework and experiment) that provides specific instructions for using gas chromatographs, fluorometers, a nuclear magnetic resonance spectrometer, an atomic absorption spectrophotometer, and an infrared spectrometer to collect replicate measurements and a framework for calculating the noise level, baseline, signal level, signal-to-noise ratio (SNR), and the signal thresholds for the limits of detection and quantitation (LOD and LOQ). With these figures of merit, students can graphically visualize the relationship between these parameters and the measured data. Also instructive is the graphical comparison between a single measurement and an ensemble averaged measurement where the baseline noise is visibly attenuated
Bridgewater College, Photograph of Rufus D. King, President Warren D. Bowman and Dean John W. Boitnott, undated
No full textArchival photograph from Bridgewater College Special Collectionshttps://digitalcommons.bridgewater.edu/k_last_name_individuals_photos/1000/thumbnail.jp
Bridgewater College, Photograph with Richard Bellows, Liz Kulnis and Brydon DeWitt, undated
No full textArchival photograph from Bridgewater College Special Collectionshttps://digitalcommons.bridgewater.edu/d_last_name_individuals_photos/1000/thumbnail.jp
Bridgewater College, Photograph of Dr. John Barr at the pipe organ, undated
No full textArchival photograph from Bridgewater College Special Collectionshttps://digitalcommons.bridgewater.edu/b_last_name_individuals_photos/1068/thumbnail.jp
Bridgewater College, Portrait of Professor Daniel W. Bly, undated
No full textArchival photograph from Bridgewater College Special Collectionshttps://digitalcommons.bridgewater.edu/b_last_name_individuals_photos/1056/thumbnail.jp
Bridgewater College, Photograph of J. Alaric Bowman and others at an event, undated
No full textArchival photograph from Bridgewater College Special Collectionshttps://digitalcommons.bridgewater.edu/b_last_name_individuals_photos/1072/thumbnail.jp