Quantitative genomics of locomotor behavior in Drosophila melanogaster

The locomotor behavior of Drosophila melanogaster was quantified in a large population of inbred lines derived from a single natural population, showing that many pleiotropic genes show correlated transcriptional responses to multiple behaviors

Heritable Variation in Garter Snake Color Patterns in Postglacial Populations

Global climate change is expected to trigger northward shifts in the ranges of natural populations of plants and animals, with subsequent effects on intraspecific genetic diversity. Investigating how genetic diversity is patterned among populations that arose following the last Ice Age is a promising method for understanding the potential future effects of climate change. Theoretical and empirical work has suggested that overall genetic diversity can decrease in colonial populations following rapid expansion into postglacial landscapes, with potential negative effects on the ability of populations to adapt to new environmental regimes. The crucial measure of this genetic variation and a population's overall adaptability is the heritable variation in phenotypic traits, as it is this variation that mediates the rate and direction of a population's multigenerational response to selection. Using two large full-sib quantitative genetic studies (NManitoba = 144; NSouth Dakota = 653) and a smaller phenotypic analysis from Kansas (NKansas = 44), we compared mean levels of pigmentation, genetic variation and heritability in three pigmentation traits among populations of the common garter snake, Thamnophis sirtalis, along a north-south gradient, including a postglacial northern population and a putative southern refuge population. Counter to our expectations, we found that genetic variance and heritability for the three pigmentation traits were the same or higher in the postglacial population than in the southern population

Phenology of Drosophila species across a temperate growing season and implications for behavior

Data have been deposited in Dryad, https://doi.org/10.5061/dryad.1bc102k.Drosophila community composition is complex in temperate regions with different abundance of flies and species across the growing season. Monitoring Drosophila populations provides insights into the phenology of both native and invasive species. Over a single growing season, we collected Drosophila at regular intervals and determined the number of individuals of the nine species we found in Kansas, USA. Species varied in their presence and abundance through the growing season with peak diversity occurring after the highest seasonal temperatures. We developed models for the abundance of the most common species, Drosophila melanogaster, D. simulans, D. algonquin, and the recent invasive species, D. suzukii. These models revealed that temperature played the largest role in abundance of each species across the season. For the two most commonly studied species, D. melanogaster and D. simulans, the best models indicate shifted thermal optima compared to laboratory studies, implying that fluctuating temperature may play a greater role in the physiology and ecology of these insects than indicated by laboratory studies, and should be considered in global climate change studies.Kansas State Biology Graduate Student Association Research GrantKU EEB GRF 210508

Quantitative Genomics of Aggressive Behavior in Drosophila melanogaster

Aggressive behavior is important for animal survival and reproduction, and excessive aggression is an enormous social and economic burden for human society. Although the role of biogenic amines in modulating aggressive behavior is well characterized, other genetic mechanisms affecting this complex behavior remain elusive. Here, we developed an assay to rapidly quantify aggressive behavior in Drosophila melanogaster, and generated replicate selection lines with divergent levels of aggression. The realized heritability of aggressive behavior was approximately 0.10, and the phenotypic response to selection specifically affected aggression. We used whole-genome expression analysis to identify 1,539 probe sets with different expression levels between the selection lines when pooled across replicates, at a false discovery rate of 0.001. We quantified the aggressive behavior of 19 mutations in candidate genes that were generated in a common co-isogenic background, and identified 15 novel genes affecting aggressive behavior. Expression profiling of genetically divergent lines is an effective strategy for identifying genes affecting complex traits

Measurement of Liquid Core Length of a Coaxial Two-fluid Spray

Shadowgraphs, tube-source X-ray radiographs, and synchrotron X-ray radiographs from a coaxial two-fluid spray are analyzed to measure the liquid core length of the spray. Two flow conditions: Rel = 1,100, Reg = 21,300, We = 40, and Rel = 1,100, Reg = 46,700, We = 196 are investigated. The standard deviation of the fluctuating intensity values are calculated and analyzed to estimate the liquid core length. Additionally, the largest connected domain is used to find an instantaneous breakup position of the spray. The results show that the high standard deviation region is related to the ligament development region, and the instantaneous position identifies ligament formation in the spray

Predictors of Neonatal Sepsis in Rural Karnataka, India

Background: Neonatal sepsis can present with subtle signs but have a fulminant and fatal course if not recognised and treated early. Many practitioners in resource-poor settings are forced to empirically manage infants at risk for sepsis without access to blood cultures. We sought to identify predictors of poor outcomes in infants with suspected sepsis at a hospital in rural Karnataka, India. Materials and Methods: This was an observational study of infants aged zero to 30 days who were admitted from January to December 2011 with a diagnosis of presumed bacterial sepsis. We extracted perinatal risk factors, gestational age, birth weight, history and physical exam at the time of admission, white blood cell count, C-reactive protein, duration of hospitalisation, disposition, and blood culture results from medical charts. Poor outcome was defined as death, positive blood culture, hospitalisation greater than five days, or transfer for higher level of care. We calculated predictive values and odds ratio for each variable using univariate logistic regression. Results: Seventy-nine infants were included; 58 (73.4%) experienced a poor outcome. Prematurity and temperature instability were significantly associated with poor outcome, with trends towards higher risk for those having very low birth weight, convulsions, a bulging fontanelle, or lethargy on admission. Nine blood cultures were positive, including seven with Staphylococcus. Conclusions: In a cohort of infants admitted for presumed sepsis in rural Karnataka, prematurity and temperature instability were associated with poor outcome. Larger studies are needed to evaluate bacterial aetiologies and determine the optimal antibiotic regimen

Single-Electron Electronics

Contains table of contents for Section 2, research goals and objectives, summary of recent work and a list of publications.Joint Services Electronics Program Grant DAAL04-95-1-0038U.S. Army Research Office Grant DAAH04-94-G-011

Artificial Atoms

Contains research goals and objectives, reports on six research projects and a list of publications.Joint Services Electronics Program Contract DAAL03-92-C-0001Joint Services Electronics Program Grant DAAH04-95-1-0038National Science Foundation Grant ECS 92-0342

The Ursinus Weekly, February 14, 1974

Week-long festival of arts slated to begin February 22 • Ursinus, at mid-winter, continues coping with problems of energy conservation • Forums set for semester • ProTheatre to present evening of avant-garde • Villanova University to sponsor tenth law review symposium • Editorial: The Myrin follies; Situation wanted: Hero • First semester Dean’s List • Letters to the editor: Union anniversary; Madison Avenue\u27s effect • Student teachers respond to experiences in area schools • SFARC News • Film Review: The Exorcist • Alumni Corner: Mike Hunter: Society drop-in • De-horn the Rams! • Jazz: Thad Jones, Mel Lewis • USGA holds elections, makes amendments and forms committees • 9-5 and still alive!https://digitalcommons.ursinus.edu/weekly/1009/thumbnail.jp

A Method of Drusen Measurement Based on the Geometry of Fundus Reflectance

BACKGROUND: The hallmarks of age-related macular degeneration, the leading cause of blindness in the developed world, are the subretinal deposits known as drusen. Drusen identification and measurement play a key role in clinical studies of this disease. Current manual methods of drusen measurement are laborious and subjective. Our purpose was to expedite clinical research with an accurate, reliable digital method. METHODS: An interactive semi-automated procedure was developed to level the macular background reflectance for the purpose of morphometric analysis of drusen. 12 color fundus photographs of patients with age-related macular degeneration and drusen were analyzed. After digitizing the photographs, the underlying background pattern in the green channel was leveled by an algorithm based on the elliptically concentric geometry of the reflectance in the normal macula: the gray scale values of all structures within defined elliptical boundaries were raised sequentially until a uniform background was obtained. Segmentation of drusen and area measurements in the central and middle subfields (1000 μm and 3000 μm diameters) were performed by uniform thresholds. Two observers using this interactive semi-automated software measured each image digitally. The mean digital measurements were compared to independent stereo fundus gradings by two expert graders (stereo Grader 1 estimated the drusen percentage in each of the 24 regions as falling into one of four standard broad ranges; stereo Grader 2 estimated drusen percentages in 1% to 5% intervals). RESULTS: The mean digital area measurements had a median standard deviation of 1.9%. The mean digital area measurements agreed with stereo Grader 1 in 22/24 cases. The 95% limits of agreement between the mean digital area measurements and the more precise stereo gradings of Grader 2 were -6.4 % to +6.8 % in the central subfield and -6.0 % to +4.5 % in the middle subfield. The mean absolute differences between the digital and stereo gradings 2 were 2.8 +/- 3.4% in the central subfield and 2.2 +/- 2.7% in the middle subfield. CONCLUSIONS: Semi-automated, supervised drusen measurements may be done reproducibly and accurately with adaptations of commercial software. This technique for macular image analysis has potential for use in clinical research