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AN INVESTIGATION INTO THE RELATIONSHIP BETWEEN THE GLOBAL COVERING FRACTION AND LUMINOSITY OF AN AGN**
No full textWe conduct a study of quasars observed by the Sloan Digital Sky Survey (to explore the relationship between the global covering fraction and the luminosity of an AGN The SDSS archives contain found 18 000 quasars with spectra between a redshift of 2 00 and 2 30 which provides spectral coverage of N V, Si IV, C IV and Mg II We find that 3000 of the objects showed absorption troughs with FWHM velocities of 500 km s 1 due to outflows intrinsic to the 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 l L l of the AGN and find a clear cutoff l L l of approximately 10 46 ergs s 1 where objects less than this cutoff show a significantly lower detection rate of outflows
EFFECT OF DELTA-9 AND DELTA-8 TETRAHYDROCANNABINOL ON DEVELOPMENTAL MORPHOLOGY OF ZEBRAFISH**
No full textMedical marijuana has been used to treat conditions such as epilepsy, nausea, pain and anxiety, and the use of it is now legal in numerous states. The primary difference between medical marijuana and recreational marijuana is in the levels of cannabidiol (CBD, higher in medical marijuana) and tetrahydrocannabinol (THC, higher in recreational marijuana). The primary psychoactive ingredient in recreational marijuana is delta 9-tetrahydrocannabinol (Δ9-THC), which has been shown to alter behavioral and locomotor responses in zebrafish embryos. Previously, we examined the effects of exposure of zebrafish embryos to Δ9-THC and found a higher death rate and shorter embryos with curved spines at the higher levels (1.25-2.5 µg/ml) of Δ9-THC compared to control embryos. Another psychoactive compound in cannabis is Δ8-THC, but because it is less potent than Δ9-THC (~50%), it is often considered “safe.” Use of Δ8-THC has risen greatly in the last few years due to the legalization of hemp-derived Δ8-THC through the 2018 US Farm Bill despite little research into its developmental effects. In this study, we compared the effects of Δ9-THC with those of Δ8-THC. Embryos were randomly divided into groups receiving 0, 0.15, 0.3, 0.6, 1.25, 2.5 and 5 µg/ml of either compound. Since stock THC solutions were in methanol, we also included a methanol-only control. Embryos were measured for length and observed for spinal curvature on day three post fertilization (3 dpf) but were kept until 5 dpf to allow further development. We monitored embryos daily to record the number dead and/or hatched. At 5 dpf, we anesthetized the embryos, fixed them in 4% paraformaldehyde and stored them in 100% methanol at 20° C for morphologic assessment of jaw structure using alcian blue staining of cartilage. Though we have yet to fully analyze the data, we are finding similar effects with Δ8-THC as with Δ9-THC: increased death rate and shorter embryos with axial curvatures. These data suggest that though Δ8-THC is legal it should not be considered safe during development
EFFECTS OF ROADWAYS ON MATE SEARCHING MOVEMENTS AND MATE LOCATION SUCCESS IN AN IMPERILED PIT VIPER (CROTALUS HORRIDUS)**
No full textA detailed understanding of animal movement behavior is fundamental to effective conservation and management. Within populations, a diversity of movement strategies can be displayed in search of critical resources, and these strategies are influenced by multiple interacting factors related to individuals and the environment. Mating partners are one critical resource that often serves as a prominent selective force shaping movement during mating seasons. For many large-bodied snakes, such as pit vipers (Viperidae: Crotalinae), male mate-searching movements are the primary determinant of mate location success. During this time, males incur significant risks associated with elevated movement. In an increasingly human-modified world, this often includes more frequent interactions with anthropogenic landscape features, such as roadways. A recent range-wide status assessment for Timber Rattlesnakes (Crotalus horridus) identified roadways among the leading threats to population persistence. More narrowly, roads are implicated in recent declines for C. horridus populations in the Piedmont ecoregion of Georgia, USA. Before effective mitigation strategies can be developed, it is critical to identify behavioral mechanisms that mediate the relative risk that roads pose to populations and individuals. Even in the absence of significant road mortality, sub-lethal effects of roads have been well documented for other wildlife but remain largely untested in snakes. In order to fill these gaps and better inform conservation, I propose an integration of radio telemetry and accelerometry to quantify the effects of proximity to roads and road interaction frequency on mate searching movements and mate location success in C. horridus from the Georgia Piedmont
COMPARATIVE STUDY ON THE CHARACTERISITCS AND PEFORMANCE OF HYDROGELS FOR NUTRIENTS RECYCLE**
No full textWastewater treatment is vital to protecting human and environmental. Interest has grown in novel applications of hydrogels in nutrients separation and recycle for water treatment utilizing their characteristics in adsorbing and desorbing aqueous nutrients. Hydrogels are polymers that contain hydrophilic functional groups which interact with water and nutrients resulting in structural swelling of the hydrogels and partitioning of nutrients between solid and aqueous phases. Hydrogels can be synthesized using various methods to improve mechanical stability and enhance the efficiency of nutrients removal. Among diverse syntheses, UV photo-initiation provides a way to incorporate different types of monomers via a high reaction efficiency and monomer conversion rate. UV photo-initiation also produces co-polymers which enables the control of hydrogel specific properties. The goal of this research is to investigate whether the co-polymer hydrogels synthesized by UV photo-initiation would deliver higher performance in removing specific nutrients from feed water and releasing the adsorbed nutrient for reuse under specific experimental conditions, in comparison with those exerted by other types of hydrogels. The hydrogels synthesized and tested in this study were microcrystalline cellulose (MCC), polyacrylamide (PAM), a hybrid of MCC and PAM (MCC-PAM), and UV photo-initiated MCC-PAM hydrogels with 1 % and 5 % MCC (UV1 and UV5, respectively). It was hypothesized that the UV photo-initiation process would render UV1 and UV5 hydrogels more feasible for application in adsorption and desorption because of the expected combined properties from cellulose and acrylamide. Experimental results showed that UV1 and UV5 retained their mechanical strength to a better extent compared to their counterparts and adsorbed medium amount of urea. MCC had the highest adsorption capacity of 61.1 mg N/g while UV5, UV1, and PAM showed 10.9, 4.7, and 4.6 mg N/g, respectively. These results are expected to be useful to design and produce hydrogles with target performance
PRELIMINARY ASSESSMENT OF COMPOST QUALITY AND SAFETY AT GEORGIA COLLEGE**
No full textThe Georgia College (GC) Green Fee Committee and Sustainability Council initiated a food recovery program with an industrial-grade composter in 2017 to decrease landfilled food waste on campus. Both pre- and post-consumer food waste from GC Dining Services is recovered, combined with untreated wood chips as a carbon source, processed through the in-vessel industrial composter, and then set out in windrows to mature. Our goal is to assess the quality and safety of the final compost product, to expand its applications both on- and off-campus. Understanding the chemical nature of the compost is vital to determining its overall nutrient level, which impacts how confidently we could apply the compost as a soil amendment for landscaping and gardening. During Fall 2020, we began sampling compost in the windrows. From August to October 2020, pH and nitrate levels were tracked weekly and assessed in situ via ion-specific electrodes. Both pH and nitrate concentrations provide reliable indicators of the overall nutrient availability and maturity of the compost. We expected the pH level to stabilize around 6.0-7.0, which is slightly acidic and ideal to ensure that nutrients are in their plant-available state. The nitrate levels were expected to increase as heterotrophic microorganisms respire carbon and nitrifying bacteria act on the available ammonium. To further investigate compost safety, we analyzed previously collected X-ray fluorescence data on total metal concentration, including heavy metals. We expect minimal heavy metal concentration since the compost inputs were obtained from a controlled source. All chemical data were compared using quality standards from the US Composting Council. We hope that continued research on our campus’s compost will help ensure the overall sustainability of the project over time
Study of a Plasma Pulse by use of the Hilbert-Huang Transform
No full textThe Hilbert-Huang Transform uses the method of empirical mode decomposition in which a signal is decomposed into multiple signals called intrinsic mode functions. A Hilbert Transform is then applied to these functions in order to obtain instantaneous frequency data. This results in a time dependent distribution of signal amplitudes, known as the Hilbert Spectrum. By applying this transform to a complex or noisy signal, the noise can be isolated and removed from the signal source. This allows for a much cleaner, easier to study signal. In this presentation, we will describe the theory behind this technique and demonstrate how it can be used to study the plasma pulse from a commercial plasma cleaning system
Solution process Spiro-MeOTAD nano-films by spin coating technique
No full textThe optical properties of 2,2′7,7′-tetrakis-(N,N-di-p-methoxyphenyl amine)-9,9′-spirobifluorene (spiro-MeOTAD) in Chlorobenzene have been investigated by UV-Vis spectroscopy. Spiro-MeOTAD is a small molecular high performance hole transport material widely used in many optoelectronic devices. Spiro-MeOTAD dissolved in Chlorobenzene reveals two absorption bands at ~ 300 and 390 nm. The thin-films have been fabricated by depositing Spiro-MeOTAD onto glass using the spin-coating method. In thin-film samples, it is found that a prominent narrow absorption peak emerges at ~ 240 nm with a broad band at ~380 nm. The film fabrication method and optoelectronic properties will be presented
Biomechanical adaptations to hive parasitism in the lesser waxmoth, Achroia grisella (Fabricius, 1794)
No full textTo understand how life stages move within and between hives, we describe biomechanical aspects of the lesser wax moth, Achroia grisella; a pest to honeybees. Peristaltic locomotion and a deformable body construction allow larvae to move through the hive. Pupae are protected by silk cases. Flight allows adult moths to mate and move from hive to hive for egg placement. To better understand these adaptations, we described the peristaltic locomotion and body deformations of the waxworms, the material properties of the pupal cocoons, and the wing morphology of the adults. Using video tracking of larvae through varying apertures, we found the larvae use an anterograde peristaltic motion and are capable of squeezing through very tight holes. This is possible because the body wall is highly elastic and posture is stabilized by high hydrostatic pressures. Material properties tests show that the silk forms cocoons of isotropic high tensile strength. Adult moths are sexually dimorphic, differing in relative wing size and their hind and forewing locking mechanisms. Egg bearing females have higher wing loading, a higher wing aspect ratio, and a more complex locking mechanism when compared to their male counterparts. This species is well-adapted to a hive parasite lifestyle
IDENTIFYING THE EFFECTS OF ALGAL TURBIDITY ON THE REPRODUCTIVE SUCCESS AND MATING BEHAVIORS OF DWARF SEAHORSES (HIPPOCAMPUS ZOSTERAE)**
No full textCoastal marine communities are particularly vulnerable to nutrients that can cause human-induced eutrophication that has been shown to alter various aspects of aquatic life. This experiment investigated the effects of algal turbidity on mating and reproductive success of the genetically monogamous dwarf seahorse (Hippocampus zosterae). To determine the effect of algal turbidity on seahorses in varied sex-ratios, each replicate consisted of six tanks, including an equal 1:1 sex ratio and two sex-biased treatments (2 females:1 male and 2 males:1 female) set up in clear and turbid water (n=3, 48 seahorses with each fish used only once). Ongoing analyses of mating behaviors using the BORIS program indicate that majority of courting occurred during the early morning hours on the second and third morning after introduction. Mate preference in the male-biased treatments was determined to be influenced by the male activity levels rather than their body size. Latency in mating had an inverse relation with the number of offspring. The latency to mate for seahorses in clear water treatments was 3.67 ± 1.36 days compared with 2.78 ± 0.64 days for the turbid water treatments. Competition in male-biased treatments led to longer latency to mating, lower reproductive success for females, and unsuccessful egg transfers. The gestation period for males did not differ across treatments and averaged around about 12 days. However, males in turbid treatments had an average of 20.4 ± 5.8 offspring compared to an average of 10.1 ± 6.9 offspring in clear water treatments. The greater reproductive success in turbid treatments may be due to adaptations in seahorses collected from Tampa Bay where animals are exposed to a wide range of turbidities throughout different seasons. Additional replicates will be conducted next summer to create a robust data set for statistical analysis to determine the effects of algae on seahorse reproduction
Validating high-frequency accelerometer field recordings of foraging behaviors in pit vipers**
No full textBiologging technology has revolutionized field studies of wildlife physiology, ecology, and behavior. Tri-axial accelerometers (ACTs), specifically, are becoming increasingly common in studies of animal behavior wherein direct observation of the subject is constrained or impossible. ACTs are small (\u3c 1 g) piezo-electric (spring-like) sensors that measure three-dimensional acceleration (upward, downward, and side-to-side) derived from subject motion. When leveraged with advanced machine learning techniques, these data can enable precise automated classification of a wide range of movement-mediated behaviors. Until recently, ACTs were largely reserved for larger-bodied organisms or those most amenable to the temporary external attachment of devices. Ongoing device miniaturization has now expanded the breadth of organisms amenable to these methods. This project aims to expand on a recently developed framework for ACT monitoring in wild-ranging snakes, a group that has been mostly overlooked in biologging applications. We are currently conducting extensive captive validation trials for robust model training and testing to enable classification of feeding behaviors, specifically strikes and ingestion of prey items, in Timber Rattlesnakes (Crotalus horridus). Following captive validation, we will translate this method to the field with a population of C. horridus in the lower Piedmont of middle Georgia to evaluate the efficacy of externally attached ACTs for remote and continuous monitoring of feeding behaviors by wild-ranging pit vipers. We envision that validation of this technique opens the door to improved interpretation of the causes and consequences of variation in individual behavior and performance, and its ultimate effects on population trajectories