38 research outputs found
Geotechnical Characterization of Success Dam for a Dam Safety Earthquake Engineering Evaluation
Success Dam, primarily a flood control and water conservation structure owned and operated by the US Army Corps of Engineers, lies in Seismic Zone 3. During construction of the dam, the impervious core trench was excavated to either weathered bedrock or older alluvium. However, the pervious outer zones of the embankment were constructed on existing in-situ materials, including recent alluvium, that were only minimally prepared. In 1992, the Corps of Engineers concluded that the state-of-practice allowed for a better understanding of the seismic response of the alluvial soils than was previously available, and a study to update the seismic stability evaluation of Success Dam was initiated. A testing program using cross hole shear wave velocity measurements and Becker Penetration Tests followed. These initial explorations showed unusual and unexpected variations in the foundation. Additional exploration programs resulted in a total of 62 Becker Penetration Tests, 20 Standard Penetration Tests, and 39 cross hole shear wave velocity holes to understand a 1,500-foot-long section of the dam foundation. The final site characterization shows an unsuspected zone of weak material deep in the foundation under the upstream shell of the dam. Only through the use of multiple field exploratory techniques was the character of this complex site adequately revealed
Spatial Humanities
This roundtable introduces spatial humanities researches at Purdue. Projects include Mapping Victorian women\u27s habitation and violence encounter by Dr. Megha Anwer; Animating material agencies with GIS data: an example from the archealogy of the Soviet Union by Dr. Elizabeth Brite; Modeling community interaction in Bronze Age Greece by Dr. Katherine Jarriel; Mapping \u27no place\u27: Eastern and Central Europe\u27s nineteenth and twentieth century phantom, indifferent, and alternative geographies by Amber Nickell
Mapping of quantitative trait loci for flesh colour and growth traits in Atlantic salmon (Salmo salar)
<p>Abstract</p> <p>Background</p> <p>Flesh colour and growth related traits in salmonids are both commercially important and of great interest from a physiological and evolutionary perspective. The aim of this study was to identify quantitative trait loci (QTL) affecting flesh colour and growth related traits in an F2 population derived from an isolated, landlocked wild population in Norway (Byglands Bleke) and a commercial production population.</p> <p>Methods</p> <p>One hundred and twenty-eight informative microsatellite loci distributed across all 29 linkage groups in Atlantic salmon were genotyped in individuals from four F2 families that were selected from the ends of the flesh colour distribution. Genotyping of 23 additional loci and two additional families was performed on a number of linkage groups harbouring putative QTL. QTL analysis was performed using a line-cross model assuming fixation of alternate QTL alleles and a half-sib model with no assumptions about the number and frequency of QTL alleles in the founder populations.</p> <p>Results</p> <p>A moderate to strong phenotypic correlation was found between colour, length and weight traits. In total, 13 genome-wide significant QTL were detected for all traits using the line-cross model, including three genome-wide significant QTL for flesh colour (Chr 6, Chr 26 and Chr 4). In addition, 32 suggestive QTL were detected (chromosome-wide P < 0.05). Using the half-sib model, six genome-wide significant QTL were detected for all traits, including two for flesh colour (Chr 26 and Chr 4) and 41 suggestive QTL were detected (chromosome-wide P < 0.05). Based on the half-sib analysis, these two genome-wide significant QTL for flesh colour explained 24% of the phenotypic variance for this trait.</p> <p>Conclusions</p> <p>A large number of significant and suggestive QTL for flesh colour and growth traits were found in an F2 population of Atlantic salmon. Chr 26 and Chr 4 presented the strongest evidence for significant QTL affecting flesh colour, while Chr 10, Chr 5, and Chr 4 presented the strongest evidence for significant QTL affecting growth traits (length and weight). These QTL could be strong candidates for use in marker-assisted selection and provide a starting point for further characterisation of the genetic components underlying flesh colour and growth.</p
Rapid Genotyping of Soybean Cultivars Using High Throughput Sequencing
Soybean (Glycine max) breeding involves improving commercially grown varieties by introgressing important agronomic traits from poor yielding accessions and/or wild relatives of soybean while minimizing the associated yield drag. Molecular markers associated with these traits are instrumental in increasing the efficiency of producing such crosses and Single Nucleotide Polymorphisms (SNPs) are particularly well suited for this task, owing to high density in the non-genic regions and thus increased likelihood of finding a tightly linked marker to a given trait. A rapid method to develop SNP markers that can differentiate specific loci between any two parents in soybean is thus highly desirable. In this study we investigate such a protocol for developing SNP markers between multiple soybean accessions and the reference Williams 82 genome. To restrict sampling frequency reduced representation libraries (RRLs) of genomic DNA were generated by restriction digestion followed by library construction. We chose to sequence four accessions Dowling (PI 548663), Dwight (PI 597386), Komata (PI200492) and PI 594538A for their agronomic importance as well as Williams 82 as a control
Disease Introduction by Aboriginal Humans in North America and the Pleistocene Extinction
While overhunting and climate change have been the major hypotheses to explain the late-Pleistocene New World megafaunal extinctions, the role of introduced disease has only received brief attention. Here, we review pre-Columbian diseases endemic to aboriginal Americans and evaluate their potential to cause large-scale mortality in Pleistocene mammals. Of the probable communicable diseases present in pre-Columbian times, we regard anthrax and tuberculosis as viable candidates. These two diseases demonstrate characteristics that could have made them deadly to immunologically naïve populations. Introduced disease, as a primary cause or interacting with overhunting and climate change, could have contributed to the decline and extirpation of Pleistocene megafauna
Disease Introduction by Aboriginal Humans in North America and the Pleistocene Extinction
While overhunting and climate change have been the major hypotheses to explain the late-Pleistocene New World megafaunal extinctions, the role of introduced disease has only received brief attention. Here, we review pre-Columbian diseases endemic to aboriginal Americans and evaluate their potential to cause large-scale mortality in Pleistocene mammals. Of the probable communicable diseases present in pre-Columbian times, we regard anthrax and tuberculosis as viable candidates. These two diseases demonstrate characteristics that could have made them deadly to immunologically naïve populations. Introduced disease, as a primary cause or interacting with overhunting and climate change, could have contributed to the decline and extirpation of Pleistocene megafauna
