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Queerblind Rhetoric in Anti-LGBTQ Politics
Anti-LGBTQ movements have gone through different phases in the United States as they have targeted homosexuality generally, same-sex marriage, and same-sex adoption. Despite the increasing acceptance and visibility of LGBTQ identities over the past twenty years, this anti-LGBTQ movement continues today, targeting what kids learn about in schools and LGBTQ youth generally. In this thesis, I research how opponents of LGBTQ rights frame their arguments in order to appeal to a more tolerant American public. Specifically, I analyze the rhetoric of anti-LGBTQ curriculum policies and anti-LGBTQ activism from 2022 and from an earlier period spanning from the 1970s to the early 2000s. I find that both policies and activism have changed their rhetoric to become more queerblind – intentionally avoiding terms or assigning value to LGBTQ identities. This queerblind theory is further developed by looking at how scholars have analyzed racially colorblind rhetoric that is more prevalent in modern-day racism and rhetoric. I argue that queerblind rhetoric has become more prevalent due to a more tolerant public and due to queerblindness being a more politically strategic opposition to the LGBTQ rights movement. </p
A Synopsis of Global Mapping of Freshwater Habitats and Biodiversity: Implications for Conservation
Accurately mapping freshwater habitats and biodiversity at high-resolutions across the globe is essential for assessing the vulnerability and threats to freshwater organisms and prioritizing conservation efforts. Since the 2000s, extensive efforts have been devoted to mapping global freshwater habitats (rivers, lakes, and wetlands), the spatial representation of which has changed dramatically over time with new geospatial data products and improved remote sensing technologies. Some of these mapping efforts, however, are still coarse representations of actual conditions. Likewise, the resolution and scope of global freshwater biodiversity compilation efforts have also increased, but are yet to mirror the spatial resolution and fidelity of mapped freshwater environments. In our synopsis, we find that efforts to map freshwater habitats have been conducted independently of those for freshwater biodiversity; subsequently, there is little congruence in the spatial representation and resolution of the two efforts. We suggest that global species distribution models are needed to fill this information gap; however, limiting data on habitat characteristics at scales that complement freshwater habitats has prohibited global high-resolution biogeography efforts. Emerging research trends, such as mapping habitat alteration in freshwater ecosystems and trait biogeography, show great promise in mechanistically linking global anthropogenic stressors to freshwater biodiversity decline and extinction risk
The Effects of a High Fat Meal on Blood Flow Regulation during Arm Exercise
A diet high in saturated fats results in endothelial dysfunction and can lead to atherosclerosis, a precursor to cardiovascular disease. Exercise training is a potent stimulus though to mitigate the negative effects of a high saturated fat diet; however, it is unclear how high-saturated fat meal (HSFM) consumption impacts blood flow regulation during a single exercise session.
PURPOSE: This study sought to examine the impact of a single HSFM on peripheral vascular function during an acute upper limb exercise bout.
METHODS: Ten young healthy individuals completed two sessions of progressive handgrip exercise. Subjects either consumed a HSFM (0.84 g of fat/kg of body weight) 4 hours prior or remained fasted before the exercise bout. Progressive rhythmic handgrip exercise (6kg, 12kg, 18kg) was performed for 3 minutes per stage at rate of 1 Hz. The brachial artery (BA) diameter and blood velocity was obtained using Doppler Ultrasound (GE Logiq e) and BA blood flow was calculated with these values.
RESULTS: BA blood flow and flow mediated dilation (normalized for shear rate) during the handgrip exercise significant increased from baseline in all workloads, but no differences were revealed in response to the HSFM consumption.
CONCLUSION: Progressive handgrip exercise augmented BA blood flow and flow mediated dilation in both testing days; however, there was no significant differences following the HSFM consumption. This suggests that upper limb blood flow regulation during exercise is unaltered by a high fat meal in young healthy individuals.https://scholarscompass.vcu.edu/gradposters/1060/thumbnail.jp
Cholinergic Modulation of Locomotion and Striatal Dopamine Release Is Mediated by α6α4* Nicotinic Acetylcholine Receptors
Dopamine (DA) release in striatum is governed by firing rates of midbrain DA neurons, striatal cholinergic tone, and nicotinic ACh
receptors (nAChRs) on DA presynaptic terminals. DA neurons selectively express α6* nAChRs, which show high ACh and nicotine
sensitivity. To help identify nAChR subtypes that control DA transmission, we studied transgenic mice expressing hypersensitive α6^(L9’S*)
receptors. α6^(L9’S) mice are hyperactive, travel greater distance, exhibit increased ambulatory behaviors such as walking, turning, and
rearing, and show decreased pausing, hanging, drinking, and grooming. These effects were mediated by α6 α4* pentamers, as α6^(L9’S) mice
lacking α4 subunits displayed essentially normal behavior. In α6^(L9’S) mice, receptor numbers are normal, but loss of α4 subunits leads to
fewer and less sensitive α6* receptors. Gain-of-function nicotine-stimulated DA release from striatal synaptosomes requires α4 subunits,
implicating α6α4β2* nAChRs in α6^(L9’S) mouse behaviors. In brain slices, we applied electrochemical measurements to study
control of DA release by α6^(L9’S) nAChRs. Burst stimulation of DA fibers elicited increased DA release relative to single action potentials
selectively in α6^(L9’S), but not WT or α4KO/ α6^(L9’S), mice. Thus, increased nAChR activity, like decreased activity, leads to enhanced
extracellular DA release during phasic firing. Bursts may directly enhance DA release from α6^(L9’S) presynaptic terminals, as there was no
difference in striatal DA receptor numbers or DA transporter levels or function in vitro. These results implicate α6α4β2* nAChRs in
cholinergic control of DA transmission, and strongly suggest that these receptors are candidate drug targets for disorders involving the
DA system
Combining reactive sputtering and rapid thermal processing for synthesis and discovery of metal oxynitrides
Recent efforts have demonstrated enhanced tailoring of material functionality with mixed anion materials, yet exploratory research with mixed anion chemistries is limited by the sensitivity of these materials to synthesis conditions. Synthesis of a particular metal oxynitride compound by traditional reactive annealing requires specific, limited ranges of both oxygen and nitrogen chemical potentials to establish equilibrium between the solid-state material and a reactive atmosphere. Using Ta–O–N as an example system, we describe a combination of reactive sputter deposition and rapid thermal processing (RTP) for synthesis of mixed anion inorganic materials. Heuristic optimization of reactive gas pressures to attain a desired anion stoichiometry is discussed, and the ability of RTP to enable amorphous to crystalline transitions without preferential anion loss is demonstrated through the controlled synthesis of nitride, oxide, and oxynitride phases
Combinatorial thin film composition mapping using three dimensional deposition profiles
Many next-generation technologies are limited by material performance, leading to increased interest in the discovery of advanced materials using combinatorial synthesis, characterization, and screening. Several combinatorial synthesis techniques, such as solution based methods, advanced manufacturing, and physical vapor deposition, are currently being employed for various applications. In particular, combinatorial magnetron sputtering is a versatile technique that provides synthesis of high-quality thin film composition libraries. Spatially addressing the composition of these thin films generally requires elemental quantification measurements using techniques such as energy-dispersive X-ray spectroscopy or X-ray fluorescence spectroscopy. Since these measurements are performed ex-situ and post-deposition, they are unable to provide real-time design of experiments, a capability that is required for rapid synthesis of a specific composition library. By using three quartz crystal monitors attached to a stage with translational and rotational degrees of freedom, we measure three-dimensional deposition profiles of deposition sources whose tilt with respect to the substrate is robotically controlled. We exhibit the utility of deposition profiles and tilt control to optimize the deposition geometry for specific combinatorial synthesis experiments
Electromagnetic Evidence that SSS17a is the Result of a Binary Neutron Star Merger
11 hours after the detection of gravitational wave source GW170817 by the
Laser Interferometer Gravitational-Wave Observatory and Virgo Interferometers,
an associated optical transient SSS17a was discovered in the galaxy NGC 4993.
While the gravitational wave data indicate GW170817 is consistent with the
merger of two compact objects, the electromagnetic observations provide
independent constraints of the nature of that system. Here we synthesize all
optical and near-infrared photometry and spectroscopy of SSS17a collected by
the One-Meter Two-Hemisphere collaboration. We find that SSS17a is unlike other
known transients. The source is best described by theoretical models of a
kilonova consisting of radioactive elements produced by rapid neutron capture
(the r-process). We find that SSS17a was the result of a binary neutron star
merger, reinforcing the gravitational wave result.Comment: 21 pages, 4 figures, accepted to Scienc
Moderation of parenting by inhibitory control in the prediction of the common and unique variance of hyperactivity-impulsivity and inattention
This study examined whether the interaction between parenting and inhibitory control predicts hyperactivity-impulsivity and inattention in 195 children. Observation data of positive parenting were collected at 4 years, and mother reports of coercive parenting at 5 years, inhibitory control at 6 years, and hyperactivity-impulsivity/inattention at 7 years were obtained. The common and unique variance of hyperactivity-impulsivity and inattention symptoms were examined as outcomes using a bifactor model. Results indicated that positive parenting practices predicted lower levels of hyperactivity-impulsivity/inattention behaviors at age 7 only when children's inhibitory control was high. These results support the vantage sensitivity model, which posits that some individuals show an increased sensitivity to positive experiences exclusively, and support the appropriateness of a targeted prevention approach in early childhood
Lateral interactions govern self-assembly of the bacterial biofilm matrix protein BslA
The soil bacterium Bacillus subtilis is a model organism to investigate the formation of biofilms, the predominant form of microbial life. The secreted protein BslA self-assembles at the surface of the biofilm to give the B. subtilis biofilm its characteristic hydrophobicity. To understand the mechanism of BslA self-assembly at interfaces, here we built a molecular model based on the previous BslA crystal structure and the crystal structure of the BslA paralogue YweA that we determined. Our analysis revealed two conserved protein-protein interaction interfaces supporting BslA self-assembly into an infinite 2-dimensional lattice that fits previously determined transmission microscopy images. Molecular dynamics simulations and in vitro protein assays further support our model of BslA elastic film formation, while mutagenesis experiments highlight the importance of the identified interactions for biofilm structure. Based on this knowledge, YweA was engineered to form more stable elastic films and rescue biofilm structure in bslA deficient strains. These findings shed light on protein film assembly and will inform the development of BslA technologies which range from surface coatings to emulsions in fast-moving consumer goods.</p
Lateral interactions govern self-assembly of the bacterial biofilm matrix protein BslA
The soil bacterium Bacillus subtilis is a model organism to investigate the formation of biofilms, the predominant form of microbial life. The secreted protein BslA self-assembles at the surface of the biofilm to give the B. subtilis biofilm its characteristic hydrophobicity. To understand the mechanism of BslA self-assembly at interfaces, here we built a molecular model based on the previous BslA crystal structure and the crystal structure of the BslA paralogue YweA that we determined. Our analysis revealed two conserved protein-protein interaction interfaces supporting BslA self-assembly into an infinite 2-dimensional lattice that fits previously determined transmission microscopy images. Molecular dynamics simulations and in vitro protein assays further support our model of BslA elastic film formation, while mutagenesis experiments highlight the importance of the identified interactions for biofilm structure. Based on this knowledge, YweA was engineered to form more stable elastic films and rescue biofilm structure in bslA deficient strains. These findings shed light on protein film assembly and will inform the development of BslA technologies which range from surface coatings to emulsions in fast-moving consumer goods.</p
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