Archeota, Fall 2017

https://scholarworks.sjsu.edu/saasc_archeota/1005/thumbnail.jp

EVALUATION OF SEPARATION METHOD ADDITIVES FOR THE RECOVERY OF BACTERIA FROM FOOD MATRICES

The microbiological testing of foods is a well-established science. Due to the severity of foodborne pathogen illnesses, the widespread use and implementation of rapid detection methods in food testing labs is increasingly important. The first step for successful testing is sampling. Surfactants have been highly used in food microbiology, but there is not much, if any, published research about the use of fatty alcohols and chemical dispersants as aids in microbial separation. The microbial extraction efficiency of Escherichia coli K12 and Listeria innocua from hot dogs, spinach, and milk was measured using chemical additives (surfactants, fatty alcohols, and a chemical dispersant) in a buffer solution. Dry matter content was calculated using the oven method to determine how clean the sample was at the end of processing. Tween 80 at 0.01% was found to be the most effective additive for microbial recovery for each food matrix examined. The addition of fatty alcohols to surfactants also showed much promise in aiding separation as well as in minimizing dry matter in the final solution. However, the use of Buffered Peptone Water as the diluting agent resulted in very high recovery percentages without the need for additives

Archeota, Fall 2016

https://scholarworks.sjsu.edu/saasc_archeota/1003/thumbnail.jp

Modulation of Bacteriophage T4 Capsid Size

AbstractBacteriophage T4 capsid assembly requires the vertex protein (gp24). Mutations that bypass this requirement are found in gene 23, which produces the major capsid protein (gp23). The latter were used to study the role of gp24 in head length control. We found that gp24 is no longer present in the capsids of several gp24 bypass mutants. We measured the capsid lengths of several of these bypass mutants, because gp24 had been reported to be implicated in headlength control. One bypass mutant (reported in 1977) produced 40–60% short headed (“petite”) phage in the presence of wild-type amounts of gp24. The bypass mutations, when combined withambermutations in gene 24, produced normal size heads in either suppressor or nonsuppressor host bacteria. When several known bypass mutations were back-crossed with wild-type phage, one-third of thebyp/24wt mutants isolated produced large amounts of petite phage, indicating that the ability to produce petite phage is a general property of the bypass mutations. Sequencing several of these bypass mutants showed that those that produced petite phage contained at least one additional missense mutation in gene 23. This suggests that gp24 itself has no direct role in head length regulation, but that in the presence of bypass 24 mutations and certain easily acquired gene 23 mutations (calledtrb) the gp23–gp24 interactions can modulate head length

SYMPOSIUM CIVIL RIGHTS OR CIVIL WANTS?

This Volume\u27s Symposium commemorates the FiftiethAnniversary of Desegregation at the University of Georgia. OnMonday, January 9, 1961, two brave, African-American students-Mr. Hamilton Holmes and Ms. Charlayne Hunter-registered forclasses on North Campus. Just three days before-and after alengthy court battle-U.S. District Judge William Bootle held inHolmes v. Danner that the students were fully qualified forimmediate admission and would already have been admitted hadit not been for their race and color. Since that historic moment,UGA and the rest of our country have taken great strides toprovide equal opportunities to all. Yet, many civil rights issuespersist in education and elsewhere.On August 26, 2011, the Georgia Law Review hosted aSymposium Conference inspired by the University\u27s yearlongcelebration of its desegregation. The Conference-entitled CivilRights or Civil Wants?-provided a venue for prominent academicsand lawyers from across the country to discuss the civil rightsissues of today and tomorrow. This Symposium Issue continuesthat discussion by providing in print the scholarship that drovethe dialogue at the Conference. Rather than take on a narrowslice of the debate, the Georgia Law Review thought this FiftiethAnniversary marked a unique opportunity to examine how oursociety\u27s conception of and dialogue on civil rights has broadenedto often include non-traditional civil rights issues. As such, inaddition to examining the current state of education, thisSymposium looks at some of today\u27s other important civil rightsissues, particularly in the contexts of immigration, information privacy, and international law after the September 11, 2011,terrorist attacks

Evaluation of Chemical Additives for the Separation and Recovery of Bacteria from Food Matrices

The microbiological testing of foods is a well-established science. Due to the severity of foodborne pathogen illnesses, the widespread use and implementation of rapid detection methods in food testing labs is increasingly important. The first step for successful testing is sampling. Surfactants have been widely used in food microbiology, but there is not much, if any, published research about the use of fatty alcohols and chemical dispersants as aids in microbial separation and recovery. The microbial extraction efficiency of Escherichia coli K12 and Listeria innocua from three representative food matrices (hot dogs, spinach, and milk) was measured using chemical additives (surfactants, fatty alcohols, and a chemical dispersant) at three concentrations, each in a buffered solution. The food matrices were inoculated with a known amount of bacteria, blended in a buffer solution, with and without additives, and then centrifuged. Data were analyzed through selective media plate counts. Results showed that Tween 80 at 0.01% was found to be the most effective additive for microbial recovery from each food matrix examined. However, the addition of fatty alcohols to surfactants significantly aided in separation and recovery, and should be further studied

A Geoarcheological Survey of the Proposed Plainview Hike and Bike Trail, Hale County, Texas

In March of 2005, the Texas Department of Transportation issued work authorization #575-01-SA005 to the Center for Archaeological Research (CAR) at the University of Texas at San Antonio to conduct a survey of areas affected by proposed improvements to the Plainview hike and bike trail in southern Plainview, Hale County, Texas. The survey was conduced under Texas Antiquities Permit #3707 between March 31 and April 7, 2005. Steve Tomka and Raymond Mauldin served as Principal Investigators. Trail construction included 2.0 miles of additional construction and 1.3 miles of improvements to existing trails. The Right-of-Way is 50 feet and extends from one to three feet below ground surface. Archeological services included a pedestrian survey, excavation of fifty-five auger tests placed no more than 100 m apart, and twenty-one Gradall trenches. Two of these trenches exposed the stratigraphy of Running Water Draw near the Plainview Site, 41HA1. Bulk samples were collected for OSL dating, diatoms analysis, and lithologic analysis for further examination of the age and stratigraphic context of the Plainview Site, which is a State Archeological Landmark, a National Landmark, and a National Register of Historic Places property. Site 41HA12 was re-examined with 10 mechanical auger tests and 1 trench, which found only recent alluvial and cultural deposition. No additional archeological sites were recorded. This report includes descriptions of the fieldwork, results of the special analyses performed on bulk sediment samples collected, and a discussion of the geomorphology of Running Water Draw with specific focus on the results from trenches excavated near the Plainview Site. The single artifact and all documents and photographs generated from this project are curated at the Center for Archaeological Research at The University of Texas at San Antonio