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Rain on the Balcony
No full textStephanie_Handlir_Harford_Community_College_Rain_on_the_Balcony_February_21__2014_at_0544PMThese images were created as part of the Hughes Remix project, a collaborative endeavor developed by UMBC's Albin O. Kuhn Library Special Collections and the Department of Visual Art to foster creative engagement with archival holdings in conjunction with the 2014 Society for Photographic Education annual conference. UMBC's Special Collections offered a selection of images from the Hughes Company Glass Negatives (http://contentdm.ad.umbc.edu/cdm/landingpage/collection/hughes) collection for SPE members and conference attendees to remix, reinvent, reinterpret, and reimagine the images in this collection of Baltimore street scenes, promotional and advertising photographs, businesses, churches, schools, monuments, factories, machinery, and portraits. Images that were created were displayed during the conference as well as on a Tumblr site and are now archived in the Special Collections. Full details of the project can be found at: http://hughes-remix.tumblr.com/overview.The original Hughes Company Glass Negatives collection can be found at: http://contentdm.ad.umbc.edu/cdm/landingpage/collection/hughe
THE HISTORY OF KINDERGARTEN IN BALTIMORE CITY, MARYLAND
No full textABSTRACT Title of Document: THE HISTORY OF KINDERGARTEN IN BALTIMORE CITY, MARYLAND Nancy Watts, M.A. Historical Studies, 2014 Directed By: Dr. Anne Rubin, Ph.D. Department Chair, History Department. Kindergarten was originally designed in 1837 to create social interaction and learning through play, became a sculpting tool for political issues at the turn of the twentieth century. This thesis explores how the changing racial and ethnic demographic of students in Baltimore affected policies related to kindergarten in the city. It shows kindergarten as a tool for social activism under the guise of teaching American patriotism. This thesis uses government legislation and secondary sources to show how education was influenced by increased immigration and segregation in Baltimore City during the mid-twentieth century. The significance of this thesis lies in its exposure of class, ethnic, and racial stratification in education at its most basic level; class in this regard refers to socioeconomic status influenced by ethnicity and race. Kindergarten, while being promoted as a way to blend cultures in a changing society, actually reinforced the disparity among classes by allowing elites to capitalize on their fears related to these differing cultures
Physical Processes in the Atmospheric Boundary Layer with Implications for Air Quality
No full textOzone (O3) is a secondary pollutant dependent on complex photochemical reactions of nitrogen oxides (NOx) and volatile organic compounds (VOCs) and is sensitive to meteorological conditions that govern solar radiation, temperature, and wind speed/direction (Stockwell, 2011). The U.S. Environmental Protection Agency (USEPA) has classified O3 as one of the six criteria pollutants that is considered harmful to both plants and human health (Hollingsworth, 2007). The current study investigates the influence of the diurnal cycle of the BL on the surface air pollutants. Specifically, it examines how the nighttime and transition period turbulence impacts the concentration of ozone at the surface and in the atmospheric column during the following day. In order to complete the study, a series of models including the Weather Research and Forecasting (WRF) model and the Comprehensive Air Quality model with Extensions (CAMx) are used to simulate atmospheric conditions in the Maryland and Texas areas. BL processes such as the minimum diffusivity or BL parameterization within CAMx are investigated. The Blackadar scheme was found to artificially suppress the nocturnal BL height and appears to be the cause of a 15 ppbv high model bias. An experiment is then conducted where a minimum BL height of 160 m and an improvement of 7% in the median model bias are found in the Maryland area. With Maryland being in a NOx-limited regime, the same process of setting a minimum height is tested in the Texas area using the YSU scheme but minimal differences produced minuscule changes in the vertical diffusivity. The use of the Ri number improved the model bias by another 5 ppbv or 13% over using the Blackadar BL scheme. A new algorithm to predict the nocturnal BL depth is implemented into the WRF YSU scheme, which scales the Ribc with the Obukhov length adding a dependency on near surface properties of the flow. The algorithm is tested using meteorological surface measurements and tower measurements, along with pollutant measurements in the Texas and Maryland areas. The median model bias improved by 10% compared to using a static critical bulk Ri number
Quantum Classification of Malware
No full textThe D-Wave architecture is a unique approach to computing which utilizes quantum annealing to solve discrete optimization problems. Applications for D-Wave machines include binary classification, complex protein-folding models, and heuristics for intractable problems such as the Traveling Salesman Problem. This thesis presents a methodology for translating the classification problem for malicious executables into an optimization problem which a D-Wave quantum annealer can solve using the Blackbox embedding software. We also investigate the viability of the D-Wave Two's application to malware analysis and prevention in current form. We show that using a D-Wave Two with Blackbox to classify malicious software is possible with cross-validation accuracy comparable to classical machine learning algorithms, but with significant overhead
The Use of Gender During the E.G. Wharton Trial
No full textIn 1871, in Baltimore, Maryland, Mrs. Elizabeth Wharton was accused of poisoning General Ketchum and arrested. The trial became a sensation in the national press, with newspapers across the country publishing daily updates on the trial. The primary reason for the attention surrounding the case was Mrs. Wharton's social status. She was extremely wealthy and well-connected in Baltimore society. After her arrest, rumors surrounding other potential victims began to surface, and many suspected her to be guilty. An examination of Wharton's trial proceedings and the surrounding press coverage reveals a defense built primarily upon Victorian notions of femininity, and ultimately the literal power of true womanhood in nineteenth century American jurisprudence. Despite overwhelming evidence of her guilt, Wharton's acquittal as an upper class white woman whose virtue was seen as beyond reproach differs significantly from contemporaneous cases of black or lower class women who were convicted of similar crimes, and largely lived beyond the definitions and protections of true womanhood
Astrocyte response to 3D microenvironments
No full textNerve injuries can be catastrophic as neurons in the adult human do not divide; therefore, neurons lost due to injury cannot be replaced by innate healing processes. Current therapeutic treatments to repair traumatic brain injury consist of rehabilitative, cellular and molecular therapies. However, these approaches target only some aspects of the injury and are not completely restorative. We propose a change in direction: to induce nerve regeneration, we focus on astrocytes, support cells in the central nervous system (CNS). We aim to harness immature astrocytes to recapitulate cues that were present in the developing brain but disrupted or lost in the adult brain injury environment. We characterized newborn mouse astrocytes in two conditions, traditional two-dimensional glass coverslips and three-dimensional (3D) hydrogels. We present quantitative data supporting that 3D culture is critical for sustaining the heterogeneity of astrocytes. We also report that fibroblast growth factor induced astrocytes encapsulated in 3D hydrogels can recapitulate developmental cues and modify the hydrogel into an environment essential for neurite outgrowth and guidance. This work is a major step towards understanding key parameters that guide astrocyte development and nerve regeneration and provides a foundation to design improved strategies for CNS injury and neurodegenerative disorders
Ram Pressure Induced Star Formation in Abell 3266
No full textAn X-ray observation of the merging galaxy cluster Abell 3266 was obtained via the ROSAT PSPC. This information, along with spectroscopic data from the WIde-field Nearby Galaxy-clusters Survey (i.e. WINGS), were used to investigate whether ram pressure is a mechanism that influences star formation. Galaxies exhibiting ongoing star formation are identified by the presence of strong Balmer lines (Hβ), known to correspond to early type stars. Older galaxies where a rapid increase in star formation has recently ceased, known as E+A galaxies, are identified by strong Hβ absorption coupled with little to no [OII] emission. The correlation between recent star formation and high ram pressure, as defined by Kapferer et al. (2009) as ≥ 5 x 10-11 dyn cm-2, was tested and lead to a contradiction of the previously held belief that ram pressure influences star formation on the global cluster scale
Optical Measurement on Quantum Cascade Lasers Using Femtosecond Pulses
No full textQuantum cascade lasers (QCLs) as the state-of-the-art mid-infrared (mid-IR) coherent sources have been greatly developed in aspects such as output power, energy efficiency and spectral purity. However, there are additional applications of QCLs in high demand, namely mode-locking, mid-IR modulation, etc. The inherent optical properties and ultrafast carrier dynamics can lead to solutions to these challenges. In this dissertation, we further characterize QCLs using mid-IR femtosecond (fs) pulses generated from a laser system consisting of a Ti:sapphire oscillator, a Ti:sapphire regenerative amplifier, an optical parametric amplifier and a difference frequency generator. We study the Kerr nonlinearity of QCLs by coupling resonant and off-resonant mid-IR fs pulses into an active QCL waveguide. We observe an increase in the spectral width of the transmitted fs pulses as the coupled mid-IR pulse power increases. This is explained by the self-phase modulation effect due to the large Kerr nonlinearity of QCL waveguides. We further confirm this effect by observing the intensity dependent far-field profile of the transmitted mid-IR pulses, showing the pulses undergo self-focusing as they propagate through the active QCL due to the intensity dependent refractive index. The finite-difference time-domain simulations of QCL waveguides with Kerr nonlinearity incorporated show similar behavior to the experimental results. The giant Kerr nonlinearity investigated here may be used to realize ultrafast pulse generation in QCLs. In addition, we temporally resolved the ultrafast mid-infrared transmission modulation of QCLs using a near-infrared pump/mid-infrared probe technique at room temperature. Two different femtosecond wavelength pumps are used with photon energy above and below the quantum well (QW) bandgap. The shorter wavelength pump modulates the mid-infrared probe transmission through interband transition assisted mechanisms, resulting in a high transmission modulation depth and several nanoseconds recovery lifetime. In contrast, pumping with a photon energy below the QW bandgap induces a smaller transmission modulation depth but much faster (several picoseconds) recovery lifetime, attributed to intersubband transition assisted mechanisms. The latter ultrafast modulation (>60 GHz) can provide a potential way to realize fast QCL based free space optical communication
Polarized Imaging Nephelometer Development and Applications on Aircraft
No full textSatellite remote sensing is the only method that is able to measure climate forcing atmospheric constituents on a global scale. Aerosols have large impacts on climate, through influencing radiation directly and through their effects on clouds. Remote sensing algorithms that deduce aerosol properties from satellite measurements of scattered sunlight rely on information about scattering patterns of aerosols. Chapter 1 places the work in context through a literature survey, and introduces and clarifies theoretical constructs necessary for understanding the remaining chapters. In order to improve our understanding of light scattering by aerosol particles, and to enable routine in situ airborne measurements of aerosol light scattering to calibrate and validate satellite algorithms, at LACO (Laboratory for Aerosols Clouds and Optics) we have developed an instrument called the Polarized Imaging Nephelometer (PI-Neph). We designed and built the portable PI-Neph instrument at UMBC (University of Maryland, Baltimore County); it directly measures the ambient volume scattering coefficient and the phase matrix elements P11, phase function, and -P12/P11, polarized phase function. Chapter 2 introduces the PI-Neph instrument, while chapter 3 lays out the calibration and data reduction algorithm. The PI-Neph employs illuminating lasers and polarization control, sampling of ambient air through an inlet, and wide field of view detection of scattered light in a scattering angle range of 3? to 176?. The instrument does not employ any moving parts, therefore it is robust and fast enough for airborne measurements. The PI-Neph first measured at a laser wavelength of 532nm, and was first deployed successfully in 2011 aboard the B200 aircraft of NASA Langley during the DEVOTE (Development and Evaluation of satellite ValidatiOn Tools by Experiments) project. In 2013, we upgraded the PI-Neph to measure at 473nm, 532nm, and 671nm nearly simultaneously. LACO has deployed the PI-Neph on a number of airborne field campaigns aboard three different NASA aircraft. This dissertation describes the PI-Neph instrument, the measurement approach, algorithm, and calibrations. Chapter 4 is a validation and error analysis case study, which quantifies the exceptionally good agreement of artificial polystyrene sphere data with Mie theory. The PS sphere validation data was collected during the 2012 deployment for the Deep Convective Clouds and Chemistry (DC3) field campaign. Residuals between Mie fit and PS data (angular mean and population standard deviation) in case of the cross fits were the following. The differences of P11 data and P11 fit (predicted by fit to -P12/P11), relative to the P11 data, was -1.9% ? 5.5%. The differences of -P12/P11 data versus -P12/P11 fit (predicted by the fit to P11) was 0.028 ? 0.062. Chapter 4 also quantifies the P11 and -P12/P11 calibration errors through a Monte Carlo simulation. At an ambient aerosol scattering coefficient of 100 Mm-1, it is estimated that the PI-Neph will measure P11 (at individual scattering angles) with relative systematic error of approximately 2.3%, and -P12/P11 with absolute systematic error of approximately 0.033. Chapter 5 presents highlights from field measurements. The DEVOTE project enabled the initial PI-Neph results, such as scattering coefficient validation via comparison to other measurements, comparison of polystyrene sphere data to Mie theory, a comparison to AERONET derived phase function, and retrieval of microphysical properties of aerosols in collaboration with Dr. Oleg Dubovik. Chapter 5 also provides an overview of DC3 data, an assessment of data quality, and quantifications of PI-Neph capabilities and noise levels. This dissertation demonstrates the capability of the PI-Neph to measure ambient levels of aerosols down to 10 Mm-1, by measurement examples from the DEVOTE and DC3 aircraft deployments. As a conclusion, an itemized list of accomplishments is given in chapter 6, along with promising future research directions
Involvement Beliefs and Behaviors of Parents Enrolled in a Community-Based Educational Program
No full textThe educational involvement practices of many Black parents are often overlooked by researchers and practitioners. In addition, the factors that lead to increased involvement among Black parents may be different than those of their non-Black peers. Thus, the goal of the two interrelated studies was to explore factors impacting educational involvement beliefs and behaviors among a population of primarily Black parents. Study 1, a quantitative study that extended the work on the Hoover-Dempsey and Sandler (2005) model of parent involvement, examined the extent to which contextual factors (parent time and energy and parent knowledge) moderate the relation between motivational (parental role construction and self-efficacy) and school-based (parental perception of school outreach) factors and involvement at school and home. The study was also designed to determine if the constructs of the model remained predictive among a racially homogeneous sample. Study 2 was a qualitative exploration of factors that influenced parent involvement behaviors among a sample of parents enrolled in a community-based educational program for the first time. In Study 1, data from 88 parents from a Maryland school district were analyzed to estimate hypothesized Hoover-Dempsey and Sandler model relations. In Study 2, data from 12 parents and program staff were analyzed using frameworks grounded in the work of Hoover-Dempsey and Sandler and Epstein (2009) to identify parent involvement themes present in their experiences. Consistent with expectations, knowledge moderated the relation between self-efficacy and home involvement and time and energy moderated the relation between school outreach and school involvement. Although the full Hoover-Dempsey and Sandler model predicted both home and school involvement, several novel relations were evidenced. Study 2 parents engaged in involvement activities often overlooked by educators such as communicating high expectations, making sacrifices to support their children, and teaching the value of education. These findings emphasize the importance of developing more inclusive, culturally-relevant conceptualizations of parent involvement than those currently employed by researchers and educators. The study also provides evidence that parental involvement efforts will be more successful if schools attend to three critical attributes: information provided to parents, educator knowledge, and educator attitudes