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AN INVESTIGATION INTO SPLICING VARIATION AND EXPRESSION PATTERNS OF INSULIN-LIKE PEPTIDE 4 (ILP4) WITHIN THE DROSOPHILA GENUS **
No full textThis ongoing research focuses on understanding the genetic mechanisms underlying acceptor site variant mutations in the insulin-signaling pathway in Drosophila, particularly within the Ilp4 gene. The study aims to elucidate the distribution of these mutations across various Drosophila species and explore sex-specific expression patterns of Ilp4. Additionally, it investigates the relative utilization of acceptor sites within the variant mutation and assesses the potential functionality of resulting isoforms. The insulin-signaling pathway plays a crucial role in regulating metabolic homeostasis in both humans and insects. Dysregulation of this pathway can lead to diseases such as diabetes mellitus and insulin resistance. In Drosophila, Ilp4 shares structural and functional similarities with mammalian insulin, making it an excellent model to study genetic variations in this pathway. This research proposes several key goals. First, it aims to uncover the genetic mechanisms behind the acceptor site variant mutation through phylogeny-aware sequence alignment. Second, it seeks to map the distribution of this mutation across different Drosophila species using genomic data. Third, the study explores sex-specific expression patterns of Ilp4 across species, employing RNA sequencing data, phylogenetic analysis, and the UCSC Genome Browser to view RNA-seq data and gene structure. Fourth, it analyzes the relative utilization of acceptor sites within the mutation using RNA-sequencing and splice junction data, validated by RT-PCR experiments. Finally, the research assesses the potential functionality of both isoform variants through prediction models and genomic data. This ongoing investigation into the Ilp4 gene\u27s acceptor site variant mutation in Drosophila contributes to our understanding of the evolution of the insulin-signaling pathway and its impact on metabolic activities and nervous system function in insects. Additionally, it sheds light on the splicing mechanisms that can lead to variations in gene products, potentially providing insights into similar processes in other organisms
EFFECTS OF EGCG ON CYP1A1 PROMOTER ACTIVITY IN MOUSE LIVER CELLS
No full textCancers are prevalent in the world today and difficult to avoid because of their many contributing factors. However, there are some well-known preventative agents present in our diet, including components from green tea extracts. One such chemical is the bioflavonoid, epigallocatechin gallate (EGCG), which inhibits carcinogenic agents, like B[a]P, from binding to the nuclear aryl hydrocarbon receptor (AhR), a transcription factor that binds to DRE sequences in the promoter region of many drug metabolizing genes. One common route of exposure for B[a]P is a diet that includes foods prepared by charcoal grilling. In cells, B[a]P binds to the AhR and activates expression of the Cyp1a1 gene. The protein made from this gene is a drug metabolizing enzyme that also causes the formation of mutagenic metabolites of B[a]P, which can mutate DNA and lead to cancer. In these experiments, we explored the ability of EGCG to inhibit activation of the Cyp1a1 promoter in Hepa 1.1 mouse hepatocytes when treated with an ethanol extract of charcoal-grilled chicken. The results from these studies show a significant decrease in promoter activity when chicken extracts were co-treated with 100 μM EGCG, as determined by a luciferase reporter assay. However, we did not detect any decrease for chicken extracts from well-done (“blackened”) samples. Additionally, we observed 10 μM EGCG treatment decreasing basal levels of Cyp1a1 promoter activity, as compared to the negative control. These data suggest that EGCG may have protective effects against carcinogens that are found in foods common in the diet, like grilled chicken
DO LARGE ENDOWMENTS AND NOBEL PRIZE LAUREATE FACULTY PRODUCE BETTER TEACHING AND LEARNING OUTCOMES?
No full textThe top universities in terms of numbers of Nobel laureates who either graduated or lectured at, are also at the top of all prestigious global university rankings. Harvard University, the richest university in the world, produced more Nobel laureates than any other university in the world, and remains one of the top universities in all global university ranking systems. Nevertheless, the notion that elite rich universities are synonymous with quality education requires a comprehensive examination. Said (2024) revealed that the wide-spread misconception that the O2 released during photosynthesis originates from the CO2 absorbed is rooted in the intuition of R. Feynman, a Nobel Prize laureate, graduated from MIT and Princeton, and lectured at Caltech. Publicly available data from course evaluations at Faculty of Arts and Sciences at Harvard University show that fourteen students evaluated teaching effectiveness of twelve different courses taught during Spring 2023 at 4.4 (on a scale of 1 to 5). Conclusions about teaching effectiveness cannot be drawn from data collected from small number of students, from a single academic term; as such, the findings cannot be generalized. At the University of Georgia, 1,785 students evaluated teaching effectiveness in 10 different biology courses taught between Summer 2004 and Fall 2014 at 4.6, rated learning experience at 4.5, and student engagement at 4.5. This paper proposes that departments or divisions use official course evaluations to present data on teaching and learning in their classrooms. Data should be driven from a minimum of 1,700 evaluations, from at least 10 representative courses taught within the past 20 years. Courses should range from introductory- to senior-, and one section of a graduate-level course. Except for the graduate-level section, data from less than five evaluations can\u27t be used due to reliability concerns
INVESTIGATING THE RELATIONSHIP BETWEEN THE GLOBAL COVERING FRACTION AND LUMINOSITY OF ACTIVE GALACTIC NUCLEI
No full textWe conduct a study of quasars observed by the Sloan Digital Sky Survey (SDSS) to explore the relationship between the global covering fraction and the luminosity of an Active Galactic Nuclei (AGN). The SDSS archives contain 1300+ quasars with spectra between the redshift of 2.70 and 3.00, which provides a spectral coverage of O VI(oxygen-6), N V(nitrogen-5), Si IV(silicon-4), and C IV(carbon-4). We find that 400+ of the objects showed absorption troughs with full width half maximum (FWHM) velocities of ~500 km/s due to outflows intrinsic to quasars. In each case, the absorption trough is evident and agrees in velocity space between all detectable ions. We compare detection fractions for each ion as a function of the λLλ of the AGN. We find O VI does not follow a trend or one similar to that of what C IV displayed in previous work
DESIGN AND APPLICATIONS OF MICROWAVE CIRCUITS IN 5G COMMUNICATION
No full textOver the last few years, the effect of wireless technology has greatly impacted the expanding tech industry at a progressive rate. Specifically, the recent surge in 5G communication has been credited for this rapid growth as this method of mass data transmission has globally been touted as the plateau of cellular networks. One of the leading proponents behind 5G telecommunication possible can be found in antennas which operate in high-frequency spectrums, an example of this is patch antennas, surprisingly at minuscule size, yet able to generate powerful signal at 5G spectrum. Our proposed antenna is implemented with a microstrip structure on FR4 dielectric substrate. In this study, using an electromagnetic simulation software (Sonnet), we have designed a model of a microwave patch antenna operating at one of the FCC-allowed 5G telecommunication bands and compared the reflection parameters of our physical antenna with the simulation antenna. We have also presented the radiative pattern of our proposed design which can be easily implemented for various wireless applications
A PRELIMINARY ANALYSIS OF BOVID MESOWEAR DATA FROM EAST TURKANA (NORTHERN KENYA) FROM 2.0 - 1.4 MILLION YEARS AGO: IMPLICATIONS FOR PLEISTOCENE HOMININ ENVIRONMENTS
No full textEastern African paleoecosystems have been a vital component of understanding the adaptive landscape inhabited by our earliest ancestors. Paleoenvironmental proxies indicate that these environments were highly dynamic during many of the most important periods in our evolutionary history. Mesowear analyses characterize herbivore tooth wear in relation to ingested foodstuffs across the life span and have provided valuable insights into the spatiotemporal nature of changing environments in eastern Africa. In this study, we use a large compilation (N = 322) of mesowear data from the family Bovidae to gather insights into the vegetation community at East Turkana, northern Kenya between 2.0 – 1.4 Ma – a period that documents the evolutionary transition between early Homo and H. erectus as well as the ecology of Paranthropus boisei (our close fossil relative). In addition, we compare two established methodologies in relation to their implications for environmental reconstruction. First, generally, we find that mesowear scores are consistent with established isotopic reconstructions of the grazer – browser spectrum and indicate that East Turkana environments were dominated by open grasslands throughout this period. However, mesowear data from the tribe Reduncini (e.g., waterbucks) indicate a more browsing diet, a pattern contra to isotopic data that indicate a complete C4 diet. We hypothesize that this is likely related to the ingestion of fresh grass (rather than arid adapted grasses) with little abrasive material, thereby minimizing tooth wear (a pattern typically related to a browsing diet). Finally, we find that both methodologies result in approximately the same environmental interpretation, however one of them provided more resolution. This preliminary analysis will be expanded upon over the next year and will undoubtedly provide novel insights into East Turkana ecosystems
The Effects of Ocean Acidification on Sea Urchin Larval Survivorship and Development in Lytechinus variegatus and Arbacia punctulata
Get PDFAccumulated carbon dioxide in the atmosphere is one of the driving factors in ocean acidification as oceanic absorption of carbon dioxide alters ocean chemistry. Lower concentrations of carbonate ions and higher concentrations of hydrogen ions in the water adversely affect marine organisms, including sea urchin larvae, that use calcium carbonate in their skeletal structures. While there is a wide body of literature demonstrating an impact of lowered pH on sea urchin larval development and survival, it is unclear if the method of pH manipulation and the species being studied influences the results. To address this, we compared two commonly employed pH manipulation methods, hydrochloric acid addition and carbon dioxide bubbling, for impacts on sea urchin development in Lytechinus variegatus. We also compared the effects of projected acidic ocean pH on larval development in L. variegatus and Arbacia punctulata. Regardless of species and pH manipulation method survivorship and aspects of skeletal features decreased as pH decreased. Counts of developmental abnormalities increased with decreasing pH. However, changes in size of specific skeletal features and prevalence of types of abnormalities observed varied with both pH manipulation method and species. Our results are consistent with previous studies showing a decrease in survivorship and skeletal size with lowered pH but indicate that the methods used to study effects of acidification on sea urchin larval development can affect the experimental outcomes and hinder making broad conclusions
Leaf Anatomy, Morphology, and Water Potential of Ipomoea brasiliensis, Croton punctatus, and Hydrocotyle bonariensis growing on the dunes of Sapelo Island, Georgia
Get PDFBarrier islands are a common geological feature found along the Atlantic and Gulf Coasts of the United States. Researchers have historically described barrier islands, and in particular dune habitats, as being physically controlled. Dune plant species experience high surface temperatures, low water-holding capacity of the substrate, sand movement, salt aerosols, high solar irradiance, and saltwater overwash. In this study, we investigated characteristics of three common plant species growing on the dunes of Sapelo Island, Georgia to understand how they survive and apparently thrive in the harsh, transient, and dynamic environment. Specifically, we examined leaf size, leaf thickness, stomatal frequency, internal leaf anatomy, and xylem water potential of Ipomoea brasiliensis, Croton punctatus, and Hydrocotyle bonariensis in relation to where individuals grew in the dune system. Leaves of plants of each species were smaller and thicker when growing on the front of dunes compared to the back of dunes. For each species, stomata were more abundant on the adaxial versus the abaxial leaf surfaces. In general, for each species, leaves growing on the front of dunes had a higher stomatal frequency than leaves growing on the back of dunes. Internal leaf anatomy for each species was equifacial with no appreciable differences in architecture between leaves growing on the front as compared to the back of dunes. Neither I. imbricata nor H. bonariensis experienced water stress over a typical summer day (the water potential of I. brasiliensis could not be measured due to the presence of latex). The difference in morphology of leaves of plants growing on the front of dunes as compared to the back of dunes illustrates classic phenotypic plasticity in relation to sun and shade leaves. The stomatal frequency and internal leaf anatomy of each species indicates that light is being processed by both the adaxial and abaxial leaf surfaces. Leaf succulence, presence of trichomes, and root architecture may allow C. punctatus to maintain a relatively high water potential. Translocation of water among ramets is a strategy used by H. bonariensis to avoid water deficit. Ipomoea brasiliensis, Croton punctatus, and Hydrocotle bonariensis demonstrate various leaf anatomy, morphology, and water conservation strategies that may serve as adaptations to the dune environment
A COMMON INVASIVE SPECIES, CHINESE PRIVET, MAY BE EXACERBATING GLOBAL CLIMATE CHANGE **
No full textChinese privet, a woody shrub native to southeast Asia, is an invasive species threatening ecosystems in the southeast United States. When the shrub establishes itself and is uncontrolled, it forms dense impenetrable thickets in places that should be occupied by native trees and shrubs. Studies show that the leaves of this shrub decompose faster than native species’ leaves. This implies that there’s potential for Chinese privet to impact the carbon cycle by affecting the soil carbon pool. The goal of this study was to determine whether the amount of organic carbon (OC) in soil under heavy Chinese privet invasion differed from that of nearby uninvaded soil. Due to Chinese privet’s faster decomposition rate, it was hypothesized that invaded soil would have significantly less OC. Soil samples (165 samples) were collected in Milledgeville, GA between November 2022 and November 2023. Soil samples separated into different depths (top 5 cm, middle 5 cm and bottom 5 cm) were collected from a forest site with heavy privet invasion and from two nearby uninvaded sites (a mixed forest stand and a pine forest stand). Percent organic matter (OM) was analyzed using the loss-on-ignition method (samples ashed at 360oC) and OC calculated as 58% of OM. One-way ANOVA was used to assess whether mean %OC differed significantly between soil depth and between sites. Results showed that there was significantly higher %OC in the uninvaded mixed forest site than the pine and privet-invaded sites. Also, %OC decreased significantly with soil depth for all sites. These findings show that under heavy and perhaps prolonged Chinese privet invasion, less carbon is stored in the soil. The implication is that if more carbon ends up in the atmosphere rather than being stored in the soil, uncontrolled invasion could be contributing to the problem of global warming
RISK FACTORS FOR FLEA INFECTION FOR A CANINE POPULATION IN COMMERCE, GA**
No full textFleas are among the most common ectoparasites of companion animals. Depending on the age, weight or breed of canine they are more or less likely to be infected with fleas. Our goal for this project was to see if age, weight, or breed has a factor in the likeliness of infection. We collected fleas from canine patients at a single hospital in Commerce, Georgia. From there, we identified the fleas and recorded the canine patient’s signalment. Overall, we collected information from 288 canine patients, with 36 of them infected by fleas. We collected and identified 323 fleas using a compound microscope. All the fleas were identified as Ctenocephalides felis. Information on canine age, breed, and size was sorted into categories and analyzed using logistic regression. By comparing canine patients with and without fleas, we can determine the importance of age, weight, and breed of the canine to the presence of fleas. This information can be used to inform owners of how susceptible their canine companions are to being infected by fleas