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Illicit Masculinity: Examining Gender Differences in Adolescent Drug Use
Get PDFWhile previous literature has examined how attitudes towards patriarchal and traditional gender norms influence alcohol and marijuana consumption, little research explores how these norms influence illicit drug use, particularly among juveniles. This research begins to explore that gap in the literature and attempts to open up further paths for examining how family structure and patriarchal norms influence the relationships between gender and crime. Using data from Monitoring the Future (N=115,492), this research examines the relationship between masculinity and the use of various illicit drugs (marijuana, n = 48,589; cocaine, n = 49,029; heroin, n = 49,094; and narcotics, n = 49,094) among U.S. high schoolers as they vary between young men and young women. Findings show statistically significant gender differences in each of the substances included in the study. Family structure has no significant effect on the gender differences in substance use, but agreement with patriarchal norms contributes to a significantly larger gender difference in marijuana, cocaine, and narcotics use when compared to disagreement with patriarchal norms. This research contributes to the literature that has focused on the gender gap in crime and provides insight into how masculinity contributes to gender differences in substance abuse
Avoiding freezer burn: Before, during, and after of a hiring freeze
Get PDFHiring freezes are a common strategy that organizations pursue during times of fiscal austerity to conserve funds. While a freeze does impact an organization, the impact is certainly less than a layoff would be. Hiring freezes, after all, are designed to be temporary, but layoffs are a permanent workforce reduction. Interim leaders may believe they have less ability to successfully address hiring freezes than those holding permanent appointments, but in reality they likely have resources at their disposal to be just as successful as other organizational leaders during such times. In this chapter, librarians will learn strategies they can employ before, during, and after a hiring freeze to speed the filling of positions when a freeze is anticipated; to make the best use of time and other resources during the freeze; and to position their organization to move creatively and effectively in filling positions when the freeze is lifted.Ye
An exploration of social determinants of health in relation to contraceptive use among young adults
Get PDFBackground: Low and inconsistent contraceptive use in young adults leads to increased unintended pregnancies. Prior research primarily focused on individual-level influences such as contraceptive attitudes and beliefs, with little consideration of social domains and contextual factors (e.g., economic and neighborhood characteristics). This dissertation project explored cross-sectional and longitudinal associations between social domains and young adult contraceptive use utilizing the Healthy People 2030 Social Determinants of Health (SDH) framework. Additionally, this dissertation also explored the mediating influence of contraceptive self-efficacy between SDH domains and contraceptive use. Methods: Proxy measures related to five SDH domains (economic stability, education, social and community context, health and health care, and neighborhood and built environment) were extracted from the National Longitudinal Study of Adolescent and Adult Health (Add Health) Wave I, II and III data to explore the association with past year ever-use and consistent use of contraception among young adults (18-26 years). Two multi-level binary logistic regressions were employed using Mplus v.8.7 to explore cross-sectional and longitudinal associations. Path analysis utilizing bias corrected bootstrapping was used for exploring mediating influence of contraceptive self-efficacy. Results: Of the 11,575 participants (Mean age: 22.02 years, (SD: 1.78); 53.77% female), 75.14% reported past year ever-use of contraception, while 45.33% were consistent contraceptive users. Cross-sectional results indicated that, out of 11 measures, six and ten measures had an empirical relationship with the past year ever-use of contraception and consistency of contraceptive use, respectively. Out of 14 key issues, in longitudinal study, six and eight key issues measured at adolescence had significant associations with past year ever-use of contraception and consistency of contraceptive use at young adulthood, respectively. Furthermore, contraceptive self-efficacy had a mediating influence between 4 key issues and past year ever-use of contraceptive use, while contraceptive self-efficacy mediated between 5 key issues and contraceptive use. The key issues were associated with Education, Social and Community Context, and Health and Health care. Conclusions: A favorable environment during adolescence and young adulthood provide a foundation for positive health behaviors. Interventions aimed to increase contraceptive use among young adults should focus on creating supporting environments during adolescence. Contraceptive self-efficacy can be targeted in short behavioral interventions to improve contraceptive use
Radar and Thermodynamic Analysis of the 6 April 2018 Monroe, LA Tornadic Supercell
Get PDFThis case study analyzes a tornadic supercell observed in northeast Louisiana as part of
the Verification of the Origins of Rotation in Tornadoes Experiment Southeast (VORTEX-SE)
on April 6—7 2018. Two mobile research radars (SR2 and SR3), one WSR-88D equivalent
(KULM) and two airborne radars (TAFT and TFOR) sampled the storm at close proximity for
~70 minutes through its mature phase, tornadogenesis at 2340 UTC, and dissipation and
subsequent ingestion into a developing MCS segment. The 4-D wind field and reflectivity from
up to five-Doppler analyses every five minutes, combined with 4-D Diabatic Lagrangian
Analysis (DLA, Ziegler 2013a,b) retrievals, enabled kinematic and thermodynamic analysis of
storm-scale boundaries leading up to, during, and after the dissipation of the 13 minute-long EF 0 tornado. Additional near-storm thermodynamic measurements from the Compact Ramen Lidar
(CRL), a P-3 aircraft-mounted downward-pointing lidar which profiles boundary layer water
vapor mixing ratio and temperature, were compared to far-field proximity soundings to provide
an accurate representation of the storm inflow environment.
Trajectory analysis using the DLA reveals that ambient environmental low-level vertical
vorticity was present in the inflow region, and additional low-level vertical vorticity appeared to
be generated by the shearing zone between the Rear-Flank Gust Front (RFGF) and inflow at the
location of tornadogenesis. Baroclinically-generated horizontal vorticity which was tilted into
vertical by downdrafts did not appear to be a significant source of vorticity for the tornado.
The kinematic and thermodynamic analysis also reveal a transient current of
baroclinically-generated low-level streamwise vorticity leading into the low-level supercell
updraft, appearing similar to the Streamwise Vorticity Current (SVC) that has been identified in
supercell simulations and observed only kinematically previously. Although the SVC did not
directly feed streamwise vorticity to the tornado-cyclone, its development coincided with
tornadogenesis.
The evolution of the supercell’s updraft and its induced surface boundaries were
investigated in the context of its unique vertical thermodynamic profile and hodograph compared
to most previous observations and simulations based on Central Plains supercells. Although the
mesoscale environment was not high-shear/low-CAPE, the Monroe supercell shared many
similarities to such storms due to meager temperature lapse rates aloft which are commonplace in
southeast severe convection events
Exploring the spatiotemporal relationships among population, land use, and water use in the United States portion of the Rio Grande River Basin
Get PDFWater use in the United States is uncertain as our climate warms and our population continues to grow. As such, it is imperative that we understand the drivers of water use in order to better plan for this future. The Rio Grande Basin (RGB) in the Southwestern United States presents an opportunity to study these drivers and the spatiotemporal relationships among them as it is a region experiencing rapid population growth in addition to being spatially heterogeneous. In this study, I use statistical analysis in R and ArcGIS Pro to examine the relationship between population, developed land cover, and agricultural land cover on water use in the RGB and how these relationships have changed from 1990 - 2015. The results of this analysis indicate that these relationships are changing both over space and time. While my work here shows a decline in water use in the Rio Grande Basin over the study period, this is attributed to only a handful of counties that experienced a steep decline in agricultural water use. This decrease in agricultural water use likely will not continue to offset the inevitable increase in domestic water use that I begin to see at the end of the study period due to growing populations in the basin. This study reveals that the relationships among population, land use and cover, and water use are dynamic, changing over both time and space, and highlights the need to look deeper into what drives water use in order to address the water needs of a rapidly expanding population
Modeling futurity: examining epistemological assumptions and political context in urbanization modeling
Get PDFComputer simulation models projecting urban expansion are useful for academics, planners, and stakeholders interested in land use patterns and their future implications. Although urban simulation models are being expanded to account for complex political dynamics present in the landscape, none have explored potential relationships between tribal borders and urbanization. In addition, each simulated output of such models examines only one possible future. It is important to recognize and critically engage with assumptions made throughout the modeling process, especially in Oklahoma where specific political processes such as land runs and allotment of tribal lands may have affected the physical landscape. Through calibrating an urban simulation model to Oklahoma, I examine any deviant spatial patterns in the landscape between tribal and non-tribal land, and critically engage with the modeling process. I do so by examining three key input datasets used to parametrize the model and I uncover epistemological assumptions that are absent of Indigenous epistemologies or are rooted in violence toward Indigenous people. In analyzing assumptions present in the three datasets, I also illustrate how alternative datasets could potentially be used to express planning priorities that align with Indigenous planning goals. This research is important because adding historic and modern political context to the modeling process may lead to widening the kinds of knowledge that are considered during the process going forward which can address questions of equity in planning processes
Generation and Control of Atomic Resonant Squeezed Light
Get PDFQuantum metrology is a new emerging technology studying of extreme sensitive and high resolution measurement based on quantum mechanical principles such as quantum entanglement and squeezing, which can potentially revolutionize modern technology for defense and national security.
Squeezed light plays a fundamental role in quantum metrology due to its reduced noise properties. Recently, it was used to increase the sensitivity of the LIGO interferometer to measure gravitational waves and provide new ways to observe the universe. Additionally, a quantum advantage has also been demonstrated in other optical devices such as plasmonic sensors and quantum imaging. However, there are still many challenges and opportunities for squeezed light to be adopted to current sensors and other systems. Therefore, the focus of this dissertation is to extend the applicability of squeezed light to atomic sensors and enable a control of quantum noise. To extend the applicability of squeezed light to atomic systems, it must have a frequency close to or on atomic resonance and a narrow linewidth to obtain an efficient interaction with atomic ensembles. Therefore, there is substantial interest in generating narrowband squeezed light on atomic resonance. The successful demonstration of atomic resonance squeezed light and the effective control of the noise properties of squeezed light can enable improved sensitivity of atomic-based sensors and deterministic transfer of the quantum correlation between two distant atomic ensembles.
In the first part of the dissertation, we present three different approaches to generate two-mode atomic resonant squeezed light with a four-wave mixing (FWM) processes in hot Rb. First, we take advantage of the proximity of the energy levels in the D1 line of Rb and Rb to demonstrate the generation of resonant squeezed light with a non-degenerate FWM in which one mode is on resonance with the D1 to transition and the other mode is on resonance with the to transition in the D1 line of Rb. For this configuration, we obtain an intensity difference squeezing level of ~dB. Moreover, the intensity difference squeezing increases to ~dB and ~dB when only one of the modes of the squeezed state is resonant with the D1 to or to transition of Rb, respectively.
Another approach used to generate resonant squeezed light is via the coupling with additional pump beam to enhance the atomic processes. We apply an optical beam to transfer population between the ground states, dress the atomic system, or saturate the transition to enhance FWM process. We measure ~dB of intensity difference squeezing when both probe and conjugate are simultaneously on resonance with the D1 to transition of Rb and ~dB of intensity difference squeezing when the probe is resonant with the D2 to transition of Rb.
While the first two approaches generate resonant squeezed light for certain transitions, there are still many transitions that we cannot reach with our techniques. To overcome this limitation, we dress the atomic state via an external DC electric field to increase the frequency tunability of the two-mode squeezed light. We design a vacuum chamber with parallel plates to apply large electric fields of up to ~kV/cm to the atomic vapor source. Our work increases the frequency tunability of the squeezed light to ~MHz, demonstrating the generation of squeezed light resonant with the D1 to transition of Rb.
In the second part of the dissertation, we discuss two different methods of controlling the properties of two-mode squeezed light to generate single-mode squeezed light and multipartite entangled light. We obtained a single-mode squeezed state with a squeezing level of ~dB by transferring the intensity quantum correlations present in the twin beams to a single beam using a feedforward technique. In the last chapter, we introduce a novel scheme to generate scalable genuine multipartite entanglement. We show configurations of the proposed scheme that can generate genuine quadpartite, hexapartite, and octapartite entanglement, which we verify through a violation of the positive partial transpose (PPT) criterion.
The generation of resonant squeezed light using atomic ensembles overcomes several experimental difficulties associated with other sources and make it possible to study the interaction between atoms and quantum states of light. Thus, our work will be a building block for quantum metrology based on squeezed light, particularly important for atomic sensing and quantum information science
Nocturnal Ascent and Low-Level Jet in a Baroclinic Zone
Get PDFA remarkable feature of the regional climatology of the central United States and the Great Plains is the existence of a nocturnal maximum in convective rainfall during the warm season. This study follows up the work of Shapiro et al. (2018; hereafter S18), in which a linear theory predicts weak but persistent ascent in the nocturnal boundary layer in baroclinic environments such as the United States Great Plains. In the S18 theory, the sudden decay of dry-convective mixing in the convective boundary layer at sunset triggers inertia-gravity waves as well as a Blackadar (1957)-like nocturnal low-level jet. For conditions typical of broad warm-season surface-based baroclinic zones extending over one or more Great Plains states, the theory predicts that air parcels in the ascent phase of the wave can rise 500 m - 1 km in 6 hours. Such large displacements may promote convective initiation and play a role in that region's well-known nocturnal maximum in convective rainfall. In the present study, the CM1 numerical model (Cloud Model 1, developed at NCAR by George Bryan) is used to examine whether the main predictions from the S18 ascent/jet theory arise in a more realistic setting. Specifically, in these simulations, the non-linear terms in the governing equations are retained, and the sudden and total shutdown of turbulence at sunset is replaced by a more realistic evening transition. The first sets of experiments focus on generating nocturnal low-level jets in a barotropic environment [no horizontal temperature gradient; free-atmosphere geostrophic wind is constant and southerly at 10 m s-1] and testing the sensitivity of those jets to a few different parameters. The resulting jets are Blackadar-like, tend to be stronger when the boundary layer is shallower and decrease in strength as the latitude increases ranging from 30oN to 45oN. After confirming that Blackadar-like nocturnal low-level jets can be generated by CM1 when run in a barotropic mode, experiments focused on the impact of baroclinicity. A baroclinic zone arises gradually in the CM1-simulated boundary layer over the course of a 4-day integration period mostly through a temporally constant prescribed deficit in the moisture flux at the surface (a Gaussian function of x, with user-specified amplitude and length scale) which causes greater daytime heating in the center of the domain than in the region outside the baroclinic zone. Aspects of the inertia-gravity wave response predicted in S18 are present in all the simulations. In particular, the main zone of ascent that develops after the evening transition is found to slowly descend with time. The peak vertical velocity and duration of the ascent are qualitatively similar to what is predicted by the S18 theory, however the onset of the ascent is generally earlier than predicted in S18. Unlike S18, the peak vertical velocity increases as the free-atmosphere geostrophic wind gets weaker. This discrepancy may likely reflect the fact that S18 does not retain non-linear terms in the governing equations
Generalized Polynomial Superfunctors
Get PDFWe introduce a generalized notion of homogeneous strict polynomial functors defined over a superalgebra, . In particular, we define two closely related families of categories and which generalize the categories of classical homogeneous strict polynomial functors studied by Friedlander and Suslin and the categories and of homogeneous strict polynomial superfunctors defined by Axtell. In particular, we exhibit equivalences between the categories , and the categories of left supermodules for generalized Schur algebras , , respectively (the latter of which were introduced by Kleshchev and Muth). Moreover, we establish a relationship between webs for and these generalized strict polynomial functors in the form of a faithful (and full under certain assumptions on ) functor from the category of -webs to