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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
The Development, Validation, And Pilot Testing of an Instrument for Coding the Client Experience of Being Listened To
No full textIn addition to empathy, warmth, and genuineness, all psychological orientations emphasize the essential role that quality listening plays in successful therapy. However, while such therapeutic factors are universally held to be important, few tools have been designed to assess the quantity and quality of these variables. Therefore, the present research developed a novel psychotherapy coding tool designed to reliably assess the presence or absence of data reflecting the client's experience of quality listening. By creating new video-taped brief intervention sessions, this project produced both novel counseling material to code and also post-session assessment data to compare to resulting coding system scores. The Experience of Being Listened To coding system was found to have excellent interrater reliability, with an ICC of .88. The system was also moderately correlated with post sessions measures of working alliance and regard. This coding system adds to the ability of researchers, clinicians, and trainers to evaluate the extent of quality listening, in session, with the intent of modifying in-session therapist behaviors to improve the client's experience of listening in therapy
An Analysis of the Legality and Impact of Youth Curfew Laws on Criminal and Health-Related Outcomes
No full textUnderage alcohol consumption is a problem in the United States where nearly one-third of youth report first consuming alcohol before the age of 13. Currently, this amounts to at least 9.3 million underage drinkers. Although originally implemented to reduce youth crime (with mixed effectiveness) and not as a means of deterring underage drinking, juvenile curfew laws have had an effect on adolescents' behavior. These laws seek to provide general protection to youth and adults by restricting the times that children of certain ages are allowed to occupy public places or streets. These laws often contain exemptions, such as allowing youths to be accompanied by adults, to respond to an emergency, or to travel to or from school, work, or a religious service. This dissertation: (a) investigates the history of curfew laws in the United States and reviews the studies that have been done to date [Article 1]; (b) provides a legal analysis of cases involving curfew laws and offers guidance for how curfew laws can be drafted to avoid being overturned in a legal challenge [Article 2]; and, (c) examines whether curfew laws are effective at reducing underage alcohol consumption [Article 3]
The relation between depression symptoms and inflammatory markers associated with cardiovascular disease risk
No full textThe purpose of the present study was to examine the potential relation between depressive symptomatology and cardiovascular disease (CVD)-related inflammatory biomarkers in participants enrolled in the Healthy Aging in Neighborhoods of Diversity across the Lifespan Study (HANDLS). 2459 participants aged to 64 years old (M = 48 years, SD = 9.3) completed the completed the Center for Epidemiological Studies Depression scale (CES-D) and underwent blood draws to assess levels of white blood cells (WBCs). A subset of these participants (n = 210) were also assessed for levels of cytokines and C-reactive protein (CRP). The main analyses set consisted of multiple regressions with an aggregated CES-D score and the CES-D subscales of negative affect, positive affect, somatic complaints, and interpersonal relationship problems (entered separately) as predictors of CRP, total WBC count, neutrophil count, lymphocyte count, Il-1b, Il-6, Il-10, and TNF-α. Additional exploratory analyses were stratified by sex and contained CES-D score by race by poverty status interaction terms. Controlling for standard cardiovascular risk factors, results indicated no association between CES-D total score and the biomarkers; limited associations between CES-D subscales and the biomarkers, such that somatic complaints predicted WBCs and interpersonal relationship problems predicted Il-10; and complex associations between CES-D subscales, socio-demographic characteristics, and inflammatory biomarkers. It is concluded that the relation between depression and inflammation is complex and underlying pathophysiological mechanisms may distinctly differ across various population groups
Transformation of UV-filters by ozone: Reaction kinetics and removal of UV absorbance
No full textUltraviolet filters (UVFs) are used in a variety of personal care products, including sunscreens and cosmetics, to protect against ultraviolet (UV) radiation. Three of the most commonly employed UVFs are oxybenzone (OXY), octocrylene (OC), and octinoxate (OMC). While these compounds provide protection against harmful UV radiation, they also represent a unique human and ecological health risk. To address these concerns, ozone application to UVFs in water and wastewater matrices was carried out and transformation efficiency was calculated. Transformation efficiency varied with water/wastewater quality. For example, an applied ozone dose of 6 mol O3/mol OXY transformed approximately 62, 44, 23, and 13% of OXY in DI water, surface water, wastewater effluent, and raw wastewater, respectively. Second order rate constants were measured for UVF reaction with ozone; reactivity with ozone varied. Second-order rate constants for OXY k""O3,app,OXY ranged from 3.65�102 to 1.68�106 M-1s-1; for OMC, k""O3,OMC was 22(�2.14)�104 M-1s-1; and for OC, k""O3,OC was 1.56 (�0.18) M-1s-1. The characteristic UV absorbance of solutions containing UVFs was measured as a function of wavelength, pH, and treatment level providing innovative insight into ozone attack mechanisms and identification of transformation products. Several transformation products were identified for ozonation of OXY, OMC, and OC and the corresponding structures represent similar environmental concerns as the parent UVFs
A Usability study of the Pico Authentication Device: User Reactions to Pico Emulated on an Android Phone
No full textWe emulate the Pico authentication token on the Android Smartphone and evaluate its usability through a casual survey of users. In 2011, Stajano proposed Pico as a physical token-based authentication system to replace traditional passwords. As far as we know, Pico has never been implemented nor tested by users. We evaluate the usability of our emulation of Pico by a comparative study in which each user creates and authenticates herself to three online accounts twice: once using Pico, and once using passwords. The study measures the accuracy, efficiency, and satisfaction of users in these tasks. Pico offers many advantages over passwords, including human-memory- and physically-effortless[3] tasks, no typing and high security. Based on public-key cryptography, Pico's security design ensures that no credential ever leaves the Pico token unencrypted. In summer 2014 we conducted a survey with 23 subjects from the UMBC community. Each subject carried out scripted tasks involving authentication, separately using our Pico emulator and a traditional password system. We measured the time and accuracy with which subjects carried out these tasks, and asked each subject to complete a survey. The survey instrument included ten Likert-scale questions and free responses and a demographics questionnaire. We then analyzed these data to find that subjects reacted positively to the Pico emulator in their responses to the Likert questions. By statistical analysis of the reactions and measurements gathered in this study we observed that subjects found the system accurate, efficient and satisfactory. We represent these data in forms or graphs and charts organised in such a way that a comparison between the two systems for authentication is clearly seen
Schema Free Interface And the Analysis of Semantic Datasets
No full textDBpedia is a project aiming to extract structured content from the information created as part of the Wikipedia. DBpedia extracts factual information from Wikipedia pages, allowing users to find answers to questions where the information is spread across many different Wikipedia articles. This information is present in the form of RDF data that is accessed using SPARQL query language thus making it difficult for naive users to retrieve the contents from the semantic datasets available over the web like DBpedia. The schema free querying approach allows users to search information from a single semantic dataset without querying the dataset with Sparql queries. It would be convenient if we provide an interactive interface to naive users for accessing this semantic data. To achieve this, we have a schema free interface where users can insert their search query in the form of nodes and links between nodes. This interface will further sort the available semantic datasets to find the most relevant datasets to be provided to the `Schema free querying of semantic data' system. The Lucene Api implemented in Java is being used for the quick indexing and searching of the big datasets like DBpedia, DBLP, LinkedMDB to find the most relevant datasets for the user query
Virtual Circuit Provisioning in Challenged Sensor Internetworks, With Application to the Solar System Internet
No full textPlatform heterogeneity, propagation delays, and link disruptions limit the scalability of sensing internetworking architectures. I present a challenged sensor internetwork (CSI) architecture that federates networks behind an overlay abstracted from individual data link layers. The associated delay-tolerant algorithms described in this work allow message exchange over otherwise incompatible networking stacks and enable novel concepts such as the NASA Solar System Internet (SSI). Border monitoring, undersea surveillance, and the SSI exemplify the need for spatially scaling networks. Existing deployments poorly address different physical links and frequent delays/disruptions. Virtual circuits abstracted from differences in the physical, data-link, and transport layers represent a unique solution to the problems of scaling diverse networks. I describe the CSI architecture as the intersection of wireless, delay-tolerant, and heterogeneous networks and describe special characteristics of this architecture that enable useful assumptions to optimize messaging. I define an InterNetwork Routing (INR) framework that decomposes the routing function into discrete logical steps and I provide algorithms for each of these steps. An inferred Contact Graph Routing (iCGR) algorithm populates logical graphs from local nodes. A Contact Graph Routing with Extension Blocks (CGR-EB) algorithm provides a hybrid source-path algorithm for synchronizing link state along network paths. A Predictive Capacity Consumption (PCC) algorithm exploits CGR-EB data to build a congestion model. Payload Aggregation/Fragmentation (PAF) and Traffic-Shaping Contacts (TSC) algorithms condition data and place limits on the amount of internetwork traffic carried over local networks. High fidelity simulations demonstrate performance in a variety of scenarios. iCGR performs within ~15% of a perfect-knowledge system. CGR-EB has a speedup over standard approaches by 300% in stable topologies, by 3000% in unstable topologies, and by 11000% in unstable topologies with non-monotonic cost functions. PCC delivers 97% more data in congested networks over table-based approaches and 37% more data than the INR framework without the congestion model. PAF/TSC reduces message count by 43% while increasing goodput by 63%. This work enables spatially distributed, scalable internetworks managed behind a consolidated data and control plane. The principals of network semi-structure and path locality should be considered in any new sensor internetwork deployment, and particularly when considering graph-based networking at astronomical scales
Train Wreck
No full textEliana_Pisciotta__Harford_Community_College__Train_Wreck_February_21__2014_at_0659PMThese 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
Dan the Diver
No full textHenry_Aragoncillo__Dan_the_Diver_March_31__2014_at_0719AMThese 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