Digital Commons @ the Georgia Academy of Science
Not a member yet
1290 research outputs found
Sort by
GENETIC ANNOTATION AND BIOINFORMATIC ANALYSIS OF THE lin-28, Dsor1, AND rictor GENES IN DROSOPHILA WILLISTONI
No full textDrosophila melanogaster is a widely-used model organism in biological research due to the many conserved genes and pathways throughout the genome compared to various organisms, including humans. The major goal of the Genomics Education Partnership Pathways Project is to evaluate the evolution of the DNA regulatory elements of the genes of the insulin-signaling pathway within the genus Drosophila. The insulin-signalling pathway is important because it regulates glucose homeostasis in animals, allowing for proper growth and development. In order to identify the regulatory elements, it is necessary to build gene models for all 64 pathway genes across 28 species of Drosophila. The goal of the research reported here was to evaluate the evolution of three genes at different pathway positions. One hypothesis is that genes associated with proteins further along the pathway are more constrained and less likely to diverge over time. Therefore, we identified and built models for three genes at different positions in the pathway in D. willistoni, a distant relative of D. melanogaster: lin-28 (near the start of the pathway), Dsor1, and rictor (near the bottom of the pathway). Unexpectedly, the amino acid sequences predicted from the new gene models did not correspond to the genes\u27 positions in the pathway. Specifically, the percent identities between genes in the two species were 67.8% (lin-28), 94.1% (Dsor1), and 73.2% (rictor). Interestingly, the results support an alternative hypothesis that the evolution of the genes is more constrained by the number of genetic interactions: 2 (lin-28), 10 (rictor), and 50 (Dsor1)
ETHANOL EXTRACTS MADE FROM CHICKEN GRILLED WITH CHARCOAL, BUT NOT PROPANE, SHOW HIGH AHR ACTIVATION IN MOUSE LIVER CELLS
No full textBenzo[a]pyrene (B[a]P), a polycyclic aromatic hydrocarbon and agonist of the aryl hydrocarbon receptor (AhR), is produced when meat is burnt. Over consumption of burnt meat can cause increased levels of B[a]P, thus increasing AhR activation and the likelihood of developing cancer. Certain bioflavonoids have been shown to inhibit AhR activation, thus preventing overexpression of down-stream gene products, like CYP1A1. Research suggests that B[a]P is still present even in meat not considered completely burnt. This prompted the examination of different cooking methods on levels of AhR activation in cooked chicken samples. We further addressed the ability of epicatechin, a bioflavonoid found in dark chocolate, to reduce AhR activation. Mouse liver cells were exposed to ethanol extracts of charcoal-grilled or propane-grilled chicken. Epicatechin was tested over a range of concentrations (25, 50, 100, and 200µM). A CYP1A1-promoter luciferase reporter assay was used to determine AhR activity. Data indicate a significant difference in AhR activation between the charcoal grilled and propane grilled chicken (P\u3c0.001), with samples prepared with charcoal exhibiting 10.1-fold higher levels than those prepared with propane. None of the concentrations of epicatechin examined showed a significant reduction of AhR activation in the presence of charcoal-grilled chicken, however the 200 µM concentration of epicatechin alone activated the AhR 4.4-fold over the control (P\u3c0.001). Together, these results suggest that propane-grilled chicken may be a safer alternative to charcoal-grilled chicken. We are unable to provide evidence that epicatchin inhibits the AhR to act as a method of chemoprevention
PATHOLOGICAL ANALYSIS OF HAND AND WRIST BONES IN CHRYSSI (CRETE)**
No full textThe excavation of an early Christian cist grave from the island of Chryssi revealed the remains of numerous individuals. Preliminary examination of the bones in the hands and wrists show arthritis conditions such as erosion, fusion, eburnation, and expansion of the bones as well as two cases of osteochondritis dissecans. A differential diagnosis will include rheumatoid arthritis, osteoarthritis, and leprosy. Further analysis and conclusions drawn will be discussed, including the prevalence of these pathologies
INTEGRATING RADIO TELEMETRY AND ACCELEROMETRY TO EVALUATE THE EFFECTS OF ROADWAYS ON THE MOVEMENT BEHAVIOR OF TIMBER RATTLESNAKES (CROTALUS HORRIDUS)**
No full textRoadways are among the most widespread anthropogenic land use features that impact wildlife. Negative impacts include vehicle-induced mortality, habitat degradation and fragmentation, and the disruption of movement. Conversely, roadways can also create edge habitat that might offer benefits to many species. Historically, radio telemetry derived spatial data has been used to estimate the total extent of space used by individual snakes (i.e., home range size) and has represented an important tool for inferring movement-based responses to prominent landscape features, such as roads. However, the estimate of an animal’s home range size alone largely ignores the equally important temporal dimension of animal movement, as individuals can alter the frequency and duration of movements independent of spatial shifts in home range sizes. To allow for a more comprehensive evaluation of the movement response of snakes to roadways, we are using a novel integration of emerging spatial analyses and tri-axial accelerometry in Timber Rattlesnakes (Crotalus horridus) from central Georgia. The total space use of each individual will be determined by calculating seasonal home ranges and occurrence distributions (i.e. Minimum Convex Polygons, Kernel Density Estimators; dynamic Brownian Bridge Movement Models). Accelerometers will simultaneously provide long-term and continuous activity budgets to quantify “real-time” movement patterns. Generalized linear mixed effect models will be used to investigate the relationship between these spatial and temporal metrics and the mean Euclidian distance to the nearest roadway. We hope to provide a widely applicable and improved methodological framework for investigating the interactions between snakes and landscape heterogeneity
EXTRACTION OF CAROTENOIDS USING DEEP EUTECTIC SOLVENTS AS GREEN AND EFFICIENT SOLVENTS**
No full textThe extraction of bioactive compounds from natural products using conventional organic solvents can leave large traces of organic solvents behind. This can lead to pollution in the environment and can also leave traces of the organic solvents in the extracts. On top of having such a negative impact on the environment the extraction yields obtained are fairly low. It is thus important to find an alternative method of extraction that can solve these problems. Deep eutectic solvents (DESs) can be used as an alternative as they are considered more environmentally friendly, have low toxicity, low cost, and can give better extraction yields. In this study, a wide range of DESs will be synthesized for the extraction of lycopene and betacarotene from tomato paste and paprika, respectively. The experimental approaches include sonication bath, vortexing, or centrifugation to obtain a proper mixture from which the carotenoids are being extracted. The carotenoid extracts are analyzed using a UV spectrophotometer and HPLC equipment. It is expected that using a DES solvent instead of a conventional organic solvent will reduce toxicity and will also increase extraction yield because of the nonpolar properties of DES solvents. Sufficient data from this study can induce a change that can make extractions environmentally friendly
THE BEST LINEAR APPROXIMATION TO y= √x ON THE INTERVAL [0, b] USING THE MINIMAX ERROR
Get PDFThis study discusses how to find the best linear approximation y=mx+b to a fundamental function y=sqrt(x) on the interval [0,b], especially using the minimax error in Numerical Analysis. For this aim we employ two mathematical techniques: a) using the MATLAB code, positioning m and n values of the smallest maximum error on a broad range of m, and n value matrix in a rough scale and then repeatedly refining the regions in the smaller scales and b) Finding three-point fitting line to a set of non-colinear three points. We see that both results are successfully obtained and identical each other neglecting the error tolerance
BIOFILTERS FOR DRINKING WATER FILTRATION**
No full textHeavy metals and metalloids such as lead, chromium, and arsenic in drinking water have deleterious effects on human and environmental health. These heavy metals can lead to serious chronic illness and other long-term health effects. Many water sources such as lakes, rivers, and groundwater wells are heavily contaminated with these heavy metals and metalloids in the current and former mining towns of Zambia. This has left the impacted communities with limited sources of fresh, clean drinking water and a desperate need for solutions. The goal of this research is to create a low-cost and sustainable at-home filtration system that utilizes biofilters to remove heavy metal contaminates such as lead from drinking water. This paper focuses on the efficacy of two biofilters, brown algae (genus Sargassum) and Moringa seeds. To test the effectiveness of these biofilters, water samples spiked with 500 µg/l of lead were filtered with these materials, then analyzed for lead concentrations. To determine how many times the Sargassum could be used, a portion of previous dried Sargassum was placed into a lead solution, then filtered, dried, and examined for lead concentration. Preliminary results showed significant reduction (70%) in lead concentrations when the spiked water samples were treated with Sargassum, while 0% reduction was observed with Moringa. These results also showed that Sargassum can be used repeatedly without losing its lead removal efficiency. More testing is being conducted on both the algae and the Moringa seeds to also include removal of microbial contaminants. According to these results, Sargassum appears to be a viable medium for use in a filtration apparatus to remove lead from contaminated water. These algae are abundant in the ocean and can easily be grown in the lab which would make them affordable and accessible, and therefore sustainable and cost-effective
Review Of J And H Filter Brightness Of Mercury, Venus, Mars, Jupiter And Saturn
No full textThe writer has carried out J and H filter brightness measurements of the five planets Mercury, Venus, Mars, Jupiter and Saturn since April, 2014. This talk will review some of the main findings of this 7.6 year study. There are several important conclusions from this work. Firstly, the reduced magnitude of Mercury is several percent brighter when that planet is at perihelion than at aphelion. Secondly, the J – H color index increases from 0.03 magnitudes at a solar phase angle of 30 degrees to 0.53 magnitudes when the solar phase angle is 150 degrees. Thirdly, Mars is almost 0.4 magnitudes brighter at a central meridian longitude of 160° W than at 40° W. Fourthly, the J-filter reduced magnitude of Jupiter is about 0.05 magnitudes brighter at a phase angle of 0 degrees than at 11 degrees. Fifthly, Saturn is about 0.3 magnitudes brighter when its ring tilt angle is 26 degrees compared to when it is 18 degrees
Simulation Of Distributed Fault Containment Algorithm Using Randomized Scheduler
No full textFault containment is an important feature of stabilizing distributed systems. A distributed system is stabilizing if there exists a finite sequence of moves that leads to a legal configuration. Generally, a distributed system will stay in a stabilizing state once it reaches that configuration unless there is a fault. The probability of a massive failure is very low, and a single fault is more likely to occur compared to multiple failures. However, containing single failures is more important in distributed systems because of the improvement of system reliability. Fault containment algorithms we implemented helped restore the legitimate configurations of the system from any state. This paper presents some experiments we have performed in single fault scenarios using a randomized scheduler. Furthermore, we have conducted simulation experiments. The simulation results give an insight into the efficiency of our algorithms. Variations in the number of nodes and the degree of faulty node are some of the factors that have been considered in the experiments, and they were graphically and numerically analyzed to provide insightful information
REMOTE SENSING ANALYSIS OF EASTERN HEMLOCK IN RESPONSE TO THE HEMLOCK WOOLY ADELGID AND BIOLOGICAL CONTROL IN THREE NORTH GEORGIA RELEASE SITES
No full textIntroduction of the invasive insect, Adelgis tsugae (Hemlock Wooly Adelgid or HWA) has devastated the health of Tsuga canadensis (Eastern Hemlock) stands. To control this damage and facilitate the recovery of T. canadensis, biological control organisms in the form of the predatory Coleopterans, Sasajiscymnus tsugae and Laricobius nigrinus, have been released in specified Hemlock Conservation Areas (HCAs) in the north Georgia mountains. The purpose of this study was to see if we can determine, through remote sensing techniques using satellite images, if biopredatory release has had positive benefits in the hemlock health in these areas. To understand the scope of T. canadensis recovery we chose to survey three biological control release sites, located at Davidson Creek (Habersham County), Boggs Creek (Lumpkin County) and Wolfpen Gap (Union County) using modified and simple remote sensing techniques through Google Earth satellite imagery and QGIS for a nine-year period. T. canadensis identifications were confirmed initially by field survey. Computational measurements of canopy cover for three randomly selected trees at each site were acquired by hand-drawing polygons around the visible perimeter in satellite imagery and extracting associated values. Within a nine-year period, nonparametric repeated measures analysis found that canopy area of selected trees did not change significantly. Canopy area and cumulative release of biological controls were found to have strong positive correlations (p = \u3c0.001, r2 = 0.88). This study provides evidence of the likelihood that T. canadensis has reached levels of competitive plateau in forest systems and may attest to the efficacy of biological control releases on the mitigation of invasive pests. Future studies may focus on increasing sample size and comparing results with areas that have no biological control treatments