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Girls in a Swimming Pool
No full textAmy_Laughlin__Vassar_College__Academic_Computing_Consultant__Girls_in_a_Swimming_Pool_February_19__2014_at_0255PMThese 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
Untitled [Dancer and two actresses in farm field]
No full textChelsey_Lee__MICA__Student_March_29__2014_at_0632PMThese 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
Quantitation, comparison, and persistence of the diazonium ion derived purine adducts in DNA of three cyclic nitrosamines in cells.
No full textThe three cyclic nitrosamines N-nitrosomorpholine (NMOR), N-nitrosopyrrolidine (NPYR), and N-nitrosopiperidine (NPIP) are potent carcinogens and mutagens that cause tumors in many experimental animal models including rats and hamsters at various bodily sites including the liver, respiratory tract, and esophagus. The mutagenic and carcinogenic potential of these compounds, like nitrosamines in general, follows from metabolic -hydroxylation, typically mediated by P450 enzymes. The -hydroxylated compounds spontaneously decompose, with concomitant rearrangement and opening of the cyclic ring, to a reactive diazonium ion on one end of the molecule and a reactive aldehyde on the other end. The presence of this bifunctional reactivity may underlie the carcinogenic potency of these cyclic compounds. The DNA damage spectrum may include not only mono-alkylation products from irreversible diazonium ion chemistry (forming a pendent aldehyde lesion, PAL) but also the more severe cross-linking products following PAL reaction with nearby amines on DNA. Diazonium ions are very reactive electrophiles capable of irreversible reaction with heteroatoms in DNA and nucleosides. Previous researchers from our lab initially studied the test-tube reactions of the corresponding primary diazonium ion of NMOR with nucleosides and DNA to quantitate the yields of alkylation at various purine heteroatoms. Of the initial purine adducts in DNA the greatest amounts of alkylation were seen at the N7-Gua, O6-Gua, and N3-Ade heteroatoms. Following additional experiments utilizing the primary diazonium ions of NPYR and NPIP with nucleosides and DNA a relative comparison of alkylation levels between the three carcinogens was then possible. NPIP derived alkylations are mysteriously 50-80 fold lower than the qualitatively similar NMOR and NPYR yields following direct comparison under identical experimental conditions with nucleosides. The test-tube reactions with DNA also yielded puzzlingly low relative levels of NPIP alkylation, in one case as low as 100-300 fold lower than the corresponding NMOR alkylation level. The major aim of the research presented here was to extend the comparisons of NMOR, NPYR, and NPIP primary diazonium ion alkylation levels from test-tube conditions to the cellular environment where the presence of repair processes, differences in rates of diffusion, and other biologically relevant conditions may be allowed to impact on the alkylation efficiency, relative yields, and persistence of DNA damage. GM2E1 cells are a human fibroblast cell line that express rat P450 2E1, an isoform of P450 capable of metabolically activating NMOR, NPYR, and NPIP. The cells were grown in tissue culture and treated with carcinogen before isolation of the DNA and quantitation of the DNA alkylation via comparison to authentic standards on HPLC and LC-MS/MS. The first specific aim of the research, to quantitate and compare the relative alkylation levels in DNA at N7-Gua, O6-Gua, and N3-Ade, following continuous exposure of the cells to 4mM carcinogen for 24hr, 48hr, and 72hr showed that all three carcinogens have levels of alkylation that are qualitatively similar in cells relative to the differences observed in test-tube reactions. In general, yields were 0.0003-0.00003% of unadducted nucleobase (qualitatively similar to the mean of yields from test-tube experiments). Relative yields were in the order: N7-Gua ≥ O6-Gua > N3-Ade (NMOR, N3-Ade not detected); N7-Gua > O6-Gua > N3-Ade (NPYR, N3-Ade not detected), and N7-Gua > N3-Ade > O6-Gua (NPIP). In general, NMOR gives greater yields than NPIP which gives greater yields than NPYR, a stark contrast from the relative yields in test-tube reactions. The second specific aim of the research was to quantitate and compare the relative persistence of the alkylation damage mentioned above. Following 24hr exposure to carcinogen and then replacement of carcinogen containing media with carcinogen free media the cells were allowed to recover for 0hr, 24hr, and 48hr before quantitation as above. Relative yields were the same order of magnitude as the continuous exposure experiments even following cessation of carcinogen exposure. Persistence of adducts for 24hr was observed for all adducts detected and for 48hr in the case of all N7-Gua adducts, O6-Gua (NMOR), and N3-Ade (NPIP). Despite the structural similarities of the carcinogens their relative levels of persistence vary from heteroatom to heteroatom. For all adducts detected, at least 24hr of persistence was observed, potentially of mutagenic consequence. In addition to the first two specific aims, an additional set of experiments was performed to assay the presence or absence of repair of O6-Gua adducts by a specific repair protein (alkylguanine DNA alkyltransferase, AGT). Despite levels of AGT activity within GM2E1 cells being sufficient to repair methylation damage that is 200 fold higher than yields from the cyclic carcinogens, no repair of any pendent aldehyde lesions was observed under all of the experiments conducted here
Assessing the contribution of legacy sediment and mill dam storage to sediment budgets in the Piedmont of Maryland.
No full textThe disparity between watershed erosion rates and downstream sediment delivery has been an important theme in geomorphology for many decades, and the role of floodplains in sediment storage has frequently been cited. In the Piedmont province of the eastern US, upland deforestation and agricultural land use following European settlement led to deposition of thick packages of overbank sediment in valley bottoms, commonly referred to as legacy deposits. Previous authors have cited geomorphic evidence that some of this legacy sediment has been remobilized by lateral migration of channels. Recent interest has focused on the role of historic mill dams as a cause of floodplain aggradation, and on mill-dam deposits as a potentially important source of sediment exported downstream. This thesis seeks to address several outstanding questions: 1) How rapidly is sediment being remobilized from Baltimore County floodplains by channel migration and bank erosion? 2) What proportion of this sediment is derived from legacy deposits? 3) Is the presence of mill dams a necessary prerequisite for aggradation of legacy sediment? 4) How important are mill-dam deposits by comparison with other sediment sources contributing to downstream sediment yields? In order to answer these questions, we measured gross and net bank erosion rates along 25 valley reaches from 18 watersheds with drainage areas between 1.8 and 155 km2 in northern Baltimore County, Maryland, including sites with and without mill dams. We compared stream morphology from LiDAR-based digital elevation data collected in 2005 with channel positions recorded on 1:2400 scale topographic maps from 1959-1961 in order to quantify nearly 50 years of channel change. Sediment samples were collected from stream banks and bars in order to characterize bulk density and particle-size distribution for use in converting volume to mass for comparison with other sediment sources. Average annual lateral migration rates ranged from 0.06 - 0.19 m/year, which represented an annual migration of 3% (0.9-5.5%) channel width across all sites, suggesting that channel dimensions may be used as reasonable predictors of bank erosion rates. Gross bank erosion rates varied from 50 to 310 Mg/km/yr (median = 114) and were positively correlated with drainage area. Measured in-channel deposition accounted for an average of 47% (28-75%) of gross erosion, with deposition increasing in importance at larger drainage areas. Legacy sediments accounted for 6-90% of bank erosion at individual sites, represented about 60% of bank height at most exposures, and accounted for 67% of the measured gross erosion. Extrapolating the results indicated that first- and second-order streams account for 59% of total stream bank erosion from 1026 km2 of northern Baltimore County. After accounting for estimated redeposition, net stream bank sediment yields (74 Mg/km2/yr) constitute 71% of the estimated average Piedmont watershed yield (104 Mg/km2/yr). Field evidence confirmed that legacy sediments existed at sites with and without mill dams. At the reach scale, mill-dam deposits contributed an average of 14.8% more sediment per unit length than typical stream channels, but the cumulative importance of mill-dam deposits as sediment sources decreased with increasing spatial scale. Cross-scale comparisons suggest that potential sediment contributions from mill-dam deposits may peak along low- to mid-basin reaches (10-40 km2). The results suggest mill dams should not be universally regarded as dominant sources of sediment from Piedmont tributaries to the Chesapeake Bay
Goth Brunch: Documentation as Object, Event as Image
No full textGOTH BRUNCH: DOCUMENTATION AS OBJECT, EVENT AS IMAGE is an exploration of documentation as a medium unto itself with capacity for subjective experience. My research has involved synthesizing the archival processes of social media, photography, curatorial practice, and surveillance as an experiment in constructing and disseminating identity and narrative. With content informed by semi-autobiographical anecdotes, inside jokes, teen angst, image/object relations, and web culture, GOTH BRUNCH attempts to highlight the successes and failures of indexing culture, from the mundane to the profane
Evaluating the effectiveness of a nursing care clinic model in the ambulatory setting
No full textThe current research considered the effectiveness of ambulatory nursing care clinics (NCCs) in managing patients 65 years and older with diabetes mellitus. In this quasi-experimental design, patients with diabetes in ten facilities received care management in nursing care clinics. Patients in the comparison group received standard physician-based care in the remaining 24 facilities. The hypotheses were that the patients in nursing care clinics would have lower physiologic measures, lower utilization rates, and higher rates of preventive screening than patients in the comparison group. Analysis for the utilization and physiologic measures was conducted using a difference-in-differences design with ordinary least squares regression including adjustments for serial correlation, intraclass correlation, and individual fixed effects. Survival analysis was used to analyze mortality and disenrollment rates. Although some statistically significant estimated effects of the NCCs on the outcome measures were observed, the estimated effects were small and not clinically meaningful. The conclusion was that the NCCs do not impact utilization, physiologic, and process measures related to diabetes management. The study was limited by the three-year study period, the length of the time the clinics had been operational. Additional time may be necessary to see significant changes in physiologic and utilization measures as indicators of effective disease management in nursing care clinics. Although this study was focused on clinical quality measures, additional measures of success may be the cost-benefit of nursing care clinics, patient satisfaction, and staff satisfaction. The policy implication of the study is that national entities should support further research into the effectiveness of ambulatory nursing care models through a variety of funding opportunities. State entities can explore ambulatory scope of practice regulatory standardization and the impacts of such changes on healthcare quality measures
Nonparametric Bayesian Density Estimation on Riemannian Manifolds
No full textNonparametric density estimation on Riemannian surfaces is performed by inducing a prior through a logistic Gaussian process prior on the space of square integrable densities on that surface. By applying the Karhunen-Loeve representation for square integrable functions via the spectral basis obtained from the Laplace-Beltrami operator on the manifold, we are able to obtain two distinct methods for density estimation. The first method, called the Grid-Based method, estimates the density on a particular set of grid points dispersed on the manifold. The second method, called the Spectral Coefficient-Based method, estimates the coefficients of the Karhunen-Loeve representation. Since the posterior distribution is non-tractible in both cases, we perform a Metropolis-Hastings Markov Chain Monte Carlo to simulate a collection of random variables generated from the Grid-Based method's posterior distribution and the Spectral Coefficient-Based method's posterior distribution. For both methods, we develop the framework and methodology for estimation as well as illustrate examples on the circle and sphere and investigate the posterior consistency of both methods
DEATH OR HIGHER RESOLUTION: AN EXPERIMENTAL TREATISE ON PROCESSES OF INVERSION IN ART HISTORY AND DIGITAL IMAGE-MAKING IN THE CONTEXTS OF WOMEN, LOBSTERS, AND THE VANITY OF THE TECHNOLOGICAL PRECIPICE.
No full textThrough mass-produced custom objects, print and video that function as markers of performance, performance that functions as sculpture and documentary, and an art practice enacted through the body of a doppleg�nger named Lexie Mountain, my work explores crossings, inversions and systems of representation. In this document, I examine existing visual and critical structures that reinforce authenticity and authority, and bring into question methods by which meaning is placed upon the human female figure. I address issues of digital resolution and definition in image-making and comprehension, how detail informs aesthetic comprehension using examples in traditional oil painting and contemporary art, and the complex conjunctions where revisions of meaning can be made
Associations of Dietary Sodium Intake and Hyperglycemia on Resting and Stress-Reactive Blood Pressure and Underlying Hemodynamics in Blacks and Whites
No full textSustained high blood pressure (BP) or hypertension has been identified as the largest single attributable risk factor for cardiovascular and cerebrovascular death. The stark racial disparity in hypertension prevalence between black and white Americans has been documented for nearly a century and is associated with a greater burden from target end-organ damage for blacks. Chronic stress, high-sodium intake and hyperglycemia are key factors that are thought to contribute to racial disparities in hypertension. The purpose of this study was to investigate whether synergistic relations of dietary sodium intake and hyperglycemia are associated with resting and reactive BP and whether these associations differ between black and white adults. The participants were 732 (61% black; 52% below poverty status) Baltimore residents who participated in the Health Aging in Neighborhoods of Diversity Across the Life Span (HANDLS) study. It was hypothesized that hyperglycemia would moderate the influence of dietary sodium intake on resting BP and underlying hemodynamics in blacks but not in whites. Additionally, hyperglycemia was expected to moderate the influence of dietary sodium intake on BP and underlying hemodynamic reactivity to emotion provocation (anger and happy) in blacks but not in whites. Multiple linear regression analyses revealed that hyperglycemia moderated the influence of sodium intake on diastolic BP (DBP), total peripheral resistance (TPR) and cardiac index (CI) in blacks but not in whites. Blacks with hyperglycemia (within the diabetic range) who consumed higher levels of dietary sodium had higher resting DBP and TPR and lower CI compared with blacks with normal glucose levels. Mixed-effects regression models revealed that the interaction of sodium intake, hyperglycemia, and condition/curvilinear condition was not associated with cardiovascular reactivity to emotion provocation, with the exception of SBP and CI in whites during happy recall. It was discovered that the interaction of sodium intake and hyperglycemia was associated with DBP elevations across all conditions of emotion provocation within blacks. Although it was not the main focus of this investigation, it was also discovered that hyperglycemia was associated with differential patterns of CVR in blacks and whites. The results within blacks suggest that the synergistic influence of high-sodium and hyperglycemia results in higher DBP during resting conditions as well as across conditions of emotion provocation. The results within whites suggest that the synergistic influence of high-sodium and hyperglycemia result in greater myocardial reactivity to happy recall. Additionally, the present findings suggest that glycemic status is a potentially important determinant of CVR for both blacks and whites. Further research is needed to confirm whether the results observed during conditions of seated rest and emotion provocation generalize to ambulatory BP and are predictive of future development of hypertension. These findings provide preliminary support that the synergistic relation of high-sodium intake and hyperglycemia may be contributing to the high rates of hypertension in black Americans and provides a promising new direction for health disparities research
Multi-Modal Saliency Fusion for Illustrative Image Enhancement
No full textDigitally manipulated or augmented images are increasingly prevalent. Multi-sensor systems produce augmented images that integrate data into a single context. Mixed-reality images are generated from the insertion of computer generated objects into a natural scene. Digital processing for application-specific tasks (e.g., compression, network transmission) can create images distorted with processing artifacts. Augmentation of digital images can lead to the inclusion of artifacts that influence the perception of the image. In an augmented image, visual cues (e.g., depth or size cues) may be perceptually inconsistent. A feature deemed important in its local context may not be as important in the broader integrated context. Inserted synthetic objects may not possess the appropriate visual cues for proper perception of the overall scene. In compressed images, finer cues that distinguish critical features may be lost. Enhancing augmented images to add or restore visual cues can improve the image's perceptibility. This dissertation presents a framework for illustrating images to enhance critical features. The enhancements, inspired by an analysis of artists' techniques, bolster the features' perceptual cues and improve the comprehension of the augmented image. The framework uses a linear combination of image (2D), surface topology (3D), and task based saliency measures to identify the critical features in the image. Upon identification, the features are interactively enhanced using a non-photorealistic rendering (NPR) deferred illustration technique. The use of multi-modal saliency allows a visualization designer to adjust the definition of critical features. The proposed framework provides a generalized, flexible, and extensible approach to enhancing salient features in an augmented image. The framework describes a metric, the Saliency Similarity Metric (SSM), for providing feedback on how closely the salient features of the enhanced image match those of the reference image. This feedback can be used for making informed decisions on tuning the visualization. The benefits of the framework are analyzed through objective and subjective evaluations. The evaluations reveal that illustrative enhancements must be carefully applied for perceptual improvement. The framework provides the flexibility necessary to effectively tune the enhancements to a particular task, data set, or user