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ISOLATION, CHARACTERIZATION, AND BIOACTIVITY OF SECONDARY METABOLITES IN EUPATORIUM SEROTINUM **
No full textPhytochemistry, a subset of natural products chemistry, pertains to the study of chemically derived products from natural substances. Findings from this field have important applications in medicinal research due to the distinctive properties of plant metabolites. All metabolites are produced from the metabolic cycle. Primary metabolites contribute to organism growth, development, and maintenance of energy. Secondary metabolites, on the other hand, are more unique with specialized functions. The naturally defensive and healing properties of natural products correlate to the organisms\u27 secondary metabolites. These compounds are found in small quantities compared to primary metabolites and can vary greatly in structure, function, and formula depending on the plant. Harnessing and studying the properties of secondary metabolites may contribute to advanced medicine through sustainable biopharmaceutical practices. Eupatorium Serotinum serves as the specimin of interest for its fever reducing qualities. Isolation and seperation of metabolites is performed through Dry Column Vacuum Chromatography (DCVC) using solvents of various polarity. Analysis of the seperated components is then performed through High Performance Liquid Chromatography (HPLC), Gas Chromatography/Mass Spectrometry (GC/MS), and Thin Layer Chromatography (TLC). The seperated fractions are also tested for growth inhibition against E. coli bacteria strains to reveal potential antibiotic properties
SYSTEMATIC ANALYSIS OF TEMPERATURE SWING SOLVENT EXTRACTION USING VARYING OPERATION AND ANALYSIS BASES**
No full textTemperature swing solvent extraction (TSSE) for the energy-efficient and economical desalination of high-salinity brines can be further expanded by using other solvents with varied chemical structures and characteristics. TSSE utilizes a low-polarity solvent with temperature-dependent water solubility for the selective extraction of water over salt from saline feeds. Current water extraction methods involve high heat and pressure for desalination. In this research, two types of amines are used: secondary and tertiary amines, to measure water recovery efficiency. Diispropylamine, N-methylcyclohexylamine, and N-ethylcyclohexylamine represent secondary amines, and Triethylamine, N,N-dimethylcyclohexylamine, N,N-diethylcyclohexylamine and N,N-Diisopropylethylhexylamine represent tertiary amines. The temperature-dependent differential partitioning behavior of saline water in amines was controlled by adjusting the extraction/equilibrium temperature, and the separation of the amine and the raffinate led to the final product water (extraction product). Current literature provides related studies, but those adopted simple volumetric or gravimetric ratios. It was hypothesized that the interaction between solvent and brine would be dependent on the solvent:water ratio as well as the salinity and the type of the solvent. To fully evaluate the water recovery efficiency of the different amines on a molar basis, the experiment consisted of measuring the product water recovery ratios, residual salt content, and residual amine content. Overall, both groups of solvents had a different level of efficiency. As the molar ratio of solvent:water increased, the water recovery efficiency decreased; however, the incremental effect of the ratio was not proportional. It was noted that the extraction efficiency was also dependent on the specific moieties. This observation is being investigated for better understanding of the molecular interactions between water and amines. The isolation of the effects of the molecular structures including the type of substituents and degree of substitution from the apparent extraction efficiency is being performed
CONCOMITANTLY COMPUTING LATTICE PROPERTIES OF DIAMOND ANVIL CELL DESIGNED X-RAY DIFFRACTION**
No full textComputing lattice parameters of X-Ray Diffraction (XRD) experiments quickly and efficiently for generalized data is a significant advantage over single dialog programs which require additional calculations. The research presented herein defines a computational methodology utilizing MATLAB for a concomitant computation of relevant lattice parameters: lattice constant, Full Width Half Max (FWHM), strain, microstrain, and crystallinity. Methods of iterative lattice constant evaluation, Gaussian fitting, and peak area integration are performed utilizing data tables of a Diamond Anvil Cell (DAC) experiment using Cu and Ce only. For the DAC dataset of Cu and Ce, we report lattice constants computed to within 5% of the accepted values and FWHM within 0.3 2θ of actual values. This script not only offers a computational tool for analyzing DAC X-ray diffraction data but also showcases its applicability to a broader range of experimental conditions. The ability to efficiently compute lattice properties of general datasets represents a valuable contribution to the field, emphasizing the presented methodology’s potential for broader scientific applications. The results contribute to the understanding of material behavior under extreme conditions, reflecting utility in further research
CHARACTERIZATION OF FARADAY CAGES FOR HIGH FREQUENCY ELECTROMAGNETIC SHIELDING
No full textWe present the results of a study of the design and effectiveness of Faraday cages against a high-altitude electromagnetic pulse (HEMP) created by an exoatmospheric nuclear explosion. Faraday cages are metallic enclosures used to shield the interior region from electromagnetic (EM) radiation. They are used in a wide array of applications from shielding computers and sensors from EM interference to hardening electrical power substations against electromagnetic attacks and geomagnetic disturbances and serve a crucial role in digital/information security. While they are effective for low frequency electromagnetic radiation, their shielding effectiveness is degraded at high frequencies, especially in unique geometries. Often these cages are made from a metallic mesh or perforated metal plates. We challenge the common belief that a Faraday cage will be effective if the hole size is of the order of the wavelength of the electromagnetic radiation or smaller using electromagnetic simulations for cage designs with varying hole size and spacing. The simulations are performed with Ansys HFSS, an industry-leading commercial computational electromagnetic solver. We find that up to 2% of the electromagnetic field is present in the interior of a Faraday cage with a holes 500 times smaller than the wavelength of the electromagnetic radiation. While acceptable for most purposes, this would not be effective in protecting sensitive electronics against a HEMP which can result in fields over 50 kV/m. We evaluate the designs’ ability to attenuate the EM pulses and aim to optimize Faraday Cage design to contain the least amount of material while also effectively shielding broad-band pulses – especially those present in EMP attacks (i.e., in the MHz/GHz range). We also evaluate the transmission of electromagnetic energy into the enclosure due to external power wires and other electronic cabling
PEER REVIEW ON STUDENTS\u27 PROJECTS IN LARGE CLASSROOM INTRODUCTORY PHYSICS TEACHING**
No full textThis study explores the implementation of individual projects, each centered around a real-world example that can be explained or predicted by physics principles. Students present their work through video recordings, enhancing their reasoning and analytical abilities. Despite the benefits of this approach, evaluating projects in a large classroom poses a challenge. To address this issue, a peer review system was introduced to effectively grade the projects. Following the project assessments, a traditional exam was administered to evaluate the overall effectiveness of this active learning method
TRYING TO UNDERSTAND 30-PLUS YEARS OF URANUS BRIGHTNESS MEASUREMENTS
No full textThe writer and others have measured the brightness of Uranus using different photometers in the Johnson V-filter since June 1991. During this time Uranus’s south temperature latitudes faced the Sun in the early 1990s, Its equator faced the Sun in late 2007 and its north polar latitudes faced the Sun in late 2023. It is concluded that the V-filter brightness is greater when the temperate and polar latitudes face the Sun than when the equator faces the Sun. The polar areas do not appear brighter in visible light but are brighter in near-infrared light. In addition to this the polar regions undergo a transition from being a continuous large and bright polar area when the sub-solar latitude is poleward of 33° to a thin bright band when the sub-solar altitude drops below 33°
EFFECT OF COVID-19 POLICY DISCREPANCIES IN HIGH-MINORITY LONG-TERM CARE FACILITIES**
No full textThe study aim is to follow the exposure of COVID-19 in older populations living in Georgia and New York nursing homes and comparatively analyze high-minority long-term care facility outbreaks according to differing state policies, quality of nursing homes, and minority population density. High-minority long-term care facilities are more likely to provide poorer quality of care to their residents. Nursing homes, which are not routinely equipped for emergency care, faced a tremendous amount of pressure as residents contracting COVID-19 rose. The Georgia Department of Public Health was one of many state departments that routinely implemented and updated their long-term care facility guidelines according to CDC recommendations. New York policies followed similar guidelines with alterations that may have attributed to the rise of their nursing home COVID-19 cases. Current research indicates that the two states\u27 differing policies may have disproportionately affected high-minority long-term care facilities. The anticipated result has a high possibility that the state of New York may have had higher COVID-19 outbreaks in high-minority nursing homes compared to Georgia nursing homes
EFFECT OF PERINATAL CARBARYL EXPOSURE ON NICOTINE-MEDIATED LOCOMOTOR BEHAVIOR IN ADULT MICE
No full textHumans and non-human animals are exposed to carbaryl, a commonly-used pesticide, with regularity via topical application as well as through the food items that have been treated with and have absorbed this pesticide. Carbaryl disrupts the acetylcholine system associated with psychological and neuromuscular dysfunctions. Previously, we have demonstrated that carbaryl alters nicotine-mediated locomotor response in adolescence. The current study aims at evaluating its effect on adult mice. Adult female mice were exposed to either 0 or 6 mg/kg/day carbaryl for 28 days via a dosed vanilla wafer prior to breeding in order to establish a body-burden of this toxicant. Dams continued to receive a dosed vanilla wafer throughout the breeding period, throughout pregnancy, and during pup lactational development until weaning at 21 days old. On the postnatal day 60, different doses of nicotine (0, 0.1, 0.5 and 1.0 mg/kg) were administered in adult mice. Nicotine inhibited locomotor behavior in a dose dependent manner. Carbaryl-exposed mice showed higher sensitivity to nicotine compared to control mice. Female mice further exhibited more nicotine-induced locomotor impairment than that in males. Interestingly, nicotine and carbaryl effects were not observed in mice with nicotine experience during adolescence suggesting the tolerance effect. Taken together, it indicates that carbaryl may have long-term effect on acetylcholine transmission depending on nicotine using history. The underlying acetylcholine-related neurochemical mechanism altered by carbaryl should be further elucidated
SOCIAL NETWORK ANALYSIS: AN EVALUATION TOOL FOR ORGANIZATIONAL COLLABORATION
No full textSocial networks play a key role in the flow of information and resources between individuals and organizations. Network analysis can inform the flow of information and resources at a macrosystemic level. The current project involved social network analysis applied at a U.S. state-level to evaluate the level of collaboration between all organizations in Georgia involved in violence and injury prevention. The research team at Georgia State University worked with Georgia Department of Public Health staff to identify a list of all organizations in Georgia eligible for the study. Representatives from eligible organizations completed three surveys across one year that measured collaboration levels between their own organization and others, satisfaction with those collaborations, and products of combined efforts. Results identified key players in the violence prevention network, notably the Georgia Department of Public Health Injury Prevention Program and the Injury Prevention Research Center at Emory University. These organizations acted as major hubs that contacted and collaborated with many smaller organizations. Results also revealed collaborative ties that were weak or nonexistent, thus highlighting areas for growth and future collaboration between organizations. Using social network analysis, sociograms developed from the data helped enlighten the number and strength of collaborations, providing insight to the Georgia State Department of Public Health Injury Prevention Program to identify strengths in relationships between organizations and areas for outreach and growth
FLASHBULB MEMORIES AS NARRATIVE TALES
No full textFlashbulb memories (FBMs) were first described by as being photographic mental images of hearing the shocking news of an important event. However, many studies have since indicated that FBMs are not more accurate than regular memories. Instead, what makes FBMs special may be that they are often rated as more vivid and often given higher confidence ratings than ordinary memories. The objective of this study was to examine FBMs from a story-telling perspective, to see if there is anything special about FBM stories that makes them good to have and to share, even if inaccurate. The current study re-examined an established set of FBMs for the space shuttle Challenger disaster that were collected from one group of college students over three time periods: in 1986, 1988 and 1989. The current analysis was three-pronged. First, the stories were judged using common narrative analysis schemas (coherence, orientation and evaluation) to see if they changed over time to become better stories from a structural perspective. Second the narratives were judged from a listener-interest point of view, to see if the narratives changed to become more interesting over time. Finally the students’ metamemory comments about why they thought their narratives changed over time were coded to see if, like literary autobiographies, some details were omitted, while other details were added, to better express the gist of the narrator’s experience. Results showed that students consistently told coherent narratives that contained a moderate level of orienting details. Interestingly, the 1989 verbal narratives contained the fewest evaluative (emotional) comments and were judged by two coders as less interesting stories with less flash and pizzazz. The students’ metamemory comments indicated they thought their less accurate later narratives best reflected the gist of their experience and best matched the visual images they held. The limitations of comparing written and verbal narratives over time are also discussed