University of Maryland, Baltimore County
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[EB 2011, Poster and Booth Session]
No full text[Title supplied by cataloger]Marielisa Lopez & Martin Rosario at the AAA booth, Experimental Biology 2011
[EB 2011, New Members' Breakfast]
No full text[Title supplied by cataloger]New undergraduate member Anne James talks with Gary Schoenwolf, Andrea Pendleton and Dave Bolender at the New Members� Breakfast, Experimental Biology 2011
[EB 2011, Young Investigator Awards Symposium]
No full text[Title supplied by cataloger]Andrew Ewald delivering the Morphological Sciences Award Lecture at the Young Investigator Awards Symposium, Experimental Biology 2011
HPV Vaccine: From FDA Approval to School Mandate
No full textIt is estimated that 75% of the sexually active population has had an HPV infection. In June 2006 the FDA approved Gardasil, the first vaccine on the market to prevent cervical cancer by protecting against certain types of HPV infections. In 2007 there were bills in 41 state legislatures promoting the vaccination of young girls from HPV through funding, education and/or requiring vaccination as a condition of school attendance. This research examines the utility of the path-dependent model for value driven issues to evaluate the influence of state institutions on the balance of interests and the terms of legislative debate. Six states were selected for examination: California, Maryland, Massachusetts, New Mexico, Vermont and Virginia. Telephone interviews were conducted with bill sponsors and interest group representatives to assess bill sponsor motivation, the political mobilization of interest groups and the use of rhetorical resources. Content analysis was done to identify evidence of the constructs of the path-dependent model for value driven issues. The results suggest that the effects of state institutions on HPV vaccine proposals in California, Maryland and Massachusetts were greatly influenced by the political mobilization of actors in the balance of interests. Conversely, the influence of state institutions on the policy outcome of HPV vaccine proposals in Vermont and Virginia was determined by the terms of legislative debate established by bill sponsors. For most of the states in the study, the evidence suggests that the HPV vaccine mandate bills were value-driven; however, the policy trajectory in New Mexico suggests that the progression of HPV vaccines mandates in New Mexico was an interest driven issue instead of value-driven issue. The results also highlight the power of rhetorical resources as tools to garner support or bolster opposition for value-driven issues. In sum, the path-dependent model proved a useful tool in examining HPV vaccine proposals by identifying positing specific trajectories for value-driven issues. The path-dependent model lends itself as an additional lens through which policy analysts and evaluators can understand the deviations created by legislative proposals dealing with issues of morality from interest driven political process models
Information Processing Structures: Political Machines and Cloudbursting
No full textCloudbursting and Political Machines represent two manifestations of an interest in parsing and processing the vast amount of content available through electronic means. I am interested in the analysis and synthesis of information and the two pieces stem from this. Political Machines breaks down the constant flow of chatter from broadcast news networks to expose the rising level of absurdity and sensationalism present therein. Cloudbursting combines and manipulates images of natural and man-made environmental phenomenon through an algorithmic process to create a hybrid space. Both pieces take the shape of a content presentation system where audio or video clips are presented to the audience. Political Machines is a physical system that sets up an interactive and interpersonal dialog about the current political culture by drawing on ideas from tactical media, found footage, do-it-yourself and hacker cultures. Cloudbursting built visually from the aesthetic traditions of experimental film, video art, and abstract expressionism while simultaneously exploring the unique time-and-place setting of performance through the continuous manipulation of videos. Cloudbursting also explored the notion of spatial depth in projected video and the intersection between video and sculpture by segmenting and re-positioning the traditional rectangular screen in space. Both pieces incorporated a social aspect, either a playful yet confrontational one as in Political Machines or one in which the audience's role as participant or observer is constantly in flux as in Cloudbursting
Group Centric Information sharing Using Hierarchical Model
No full textTraditional security policies are often based on the concept of need to know and are typified by predefined and often rigid specifications of which principals and roles are pre-authorized to access the information. A recommendations of the 9/11 commission was to find ways to move from this traditional perspective toward one that emphasizes the need to share. Ravi Sandhu and his colleagues have developed the Group centric secure information sharing model (gSIS) as a new model that is more adaptable to highly dynamic situations requiring information sharing. We present an implementation of gSIS and demonstrate its usefulness to use-cases in information sharing in social media. Our contributions include the prototype implementation, extension to the model such as hierarchical groups and necessary and sufficient conditions, and the use of the Semantic Web language for representing the central gSIS concepts and associated data. Our framework uses a pragmatic approach of using semantic web technology to represent and reason about the hierarchy and procedural method to compute access decisions relying on the gSIS semantics
Measurement of Illness Knowledge in Parents of Children with Food Allergy
No full textThe goal of the current study was to develop a preliminary version of a measure of illness knowledge in parents of children with food allergy (The FAKT). The current study involved two phases. The first phase consisted of the construction of the FAKT; content was based on educational resources and allergist ratings of clinical importance. Items were based on allergist ratings and feedback from cognitive interviews with parents. The second phase consisted of a test of the measure with 317 mothers of children with food allergy. On the FAKT, participant total scores ranged from 32 to 88 (M = 79.28, SD = 6.67). Item difficulty and discrimination indices suggested that the FAKT contains several items that are appropriately difficult and discriminatory. Coefficient alpha was highly reliable for the FAKT (α = .868). This pilot test of the FAKT will serve as the basis for future refinements of this measure
Investigation of Carrier Dynamics and Nonlinear Effects in Quantum Cascade Lasers using Femtosecond Mid-Infrared Pulses
No full textQuantum cascade lasers (QCLs) are semiconductor lasers based on intersubband transitions and resonant tunneling, emitting mid- to far-infrared light. This dissertation used femtosecond (fs) mid-IR pulses generated by difference-frequency generation (DFG) to investigate the ultrafast carrier dynamics and nonlinear effects in QCLs. In this work, the carrier dynamics of high wall-plug efficiency designed QCLs were investigated utilizing fs mid-IR degenerate pump-probe technique. We observed ultrafast gain recovery within the first 200 fs due to the thin injector barrier inducing fast electron resonant tunneling, fast depletion from lower lasing level by two-phonon resonance design, and relaxation from the continuum region. The observed gain recovery oscillation is interpreted as electrons excited by incoming photons up to higher subbands or continuum region then falling into the next periods of active region so as to dramatically increase the gain on a short time scale. Later, slower gain recovery (2-3 picoseconds) is observed by electron transport through the injector region of the superlattice structure and tunneling into the next period of active region. Another ultraslow recovery component (hundreds of picoseconds) is likely caused by the electron heating and cooling effects as well as the collection of electrons into the lower subbands in real space and compensated by the external bias supply. The latter contribution is support by the observed positive photoconductivity with increased current and decreased voltage across the QCL. We studied the SHG signal generated by focusing different polarizations (TE and TM modes) fs mid-IR pulses into the QCLs' active core. SHG due to intersubband transitions is observed when the pump is TM polarized (SHGTM). The measured SHGTM spectrum narrows when the bias across the QCL increases due to the electron population re-distribution and subband realignment. The expected quadratic dependence of the SHGTM with mid-IR pump power is observed, but saturates at higher pump powers. The observed SHG pumped by TE polarized fs mid-IR pulses (SHGTE) is most likely generated by the bulk nonlinearity of the InP substrate. The second order nonlinearity for SHGTE is also confirmed, without observing the saturation. We estimated linear-to-nonlinear power conversion efficiency for both SHGTM and SHGTE
A SECURITY FRAMEWORK TO COPE WITH NODE MISBEHAVIORS IN MOBILE AD HOC NETWORKS
No full textA Mobile Ad-hoc NETwork (MANET) has no fixed infrastructure, and is generally composed of a dynamic set of cooperative peers. These peers share their wireless transmission power with other peers so that indirect communication can be possible between nodes that are not in the radio range of each other . The nature of MANETs, such as node mobility, unreliable transmission medium and restricted battery power, makes them extremely vulnerable to a variety of node misbehaviors. Wireless links, for instance, are generally prone to both passive eavesdropping and active intrusion. Another security concern in ad hoc networks is caused by the cooperative nature of the nodes. Attacks from external adversaries may disturb communications, but the external intruder generally cannot directly participate in the cooperative activities among the nodes because they do not possess the proper secure credentials, such as shared keys. However, compromised nodes, which are taken over by an adversary, are capable of presenting the proper secure credentials, and consequently can interfere with almost all of the network operations, including route discovery, key management and distribution, and packet forwarding. Hence, it is essential to cope with node misbehaviors so as to secure mobile ad hoc networks. In this dissertation, we address the question of how to ensure that a MANET will properly operate despite the presence of various node misbehaviors by building a holistic framework that can cope with various node misbehaviors in an intelligent and adaptive manner. The main purpose of this framework is to provide a platform so that the components that identify and respond to misbehaviors can better cooperate with each other and quickly adapt to the changes of network context. Therefore, policies are utilized in our framework in order to make those components correctly function in different network contexts. Besides the policy component, there are three other components, which fulfill the tasks of misbehavior detection, trust management, and context awareness, respectively. To validate and evaluate our proposed framework, we implement our framework based on a simulator. The specific contributions of this dissertation are: (i) Develop a framework to combine the functionalities of surveillance and detection of misbehavior, trust management, context awareness, and policy management to provide a high-level solution to cope with various misbehaviors in MANETs in an intelligent and adaptive manner; (ii) Utilize the outlier detection technique as well as the Support Vector Machine (SVM) algorithm to detect node misbehaviors, and both techniques do not require a pre-defined fix threshold for misbehavior detection; (iii) Trust is modeled in a vector instead of a single scalar so that it can reflect the trustworthiness of a node in a more accurate manner; (iv) Sense and record various contextual information, such as network status (channel busy/idle, etc.), node status (transmission buffer full/empty, battery full/low, etc.) and environmental factors (altitude, velocity, temperature, weather condition, etc.), so that we can distinguish truly malicious behaviors from faulty behaviors and also more accurately evaluate nodes' trust; (v) Specify and enforce policies in the proposed framework, which makes the framework promptly adapt to the rapidly changing network context
OLDER MEN'S KNOWLEDGE OF OSTEOPOROSIS BY RACE AND RISK FACTORS
No full textNumerous studies have explored women's knowledge of osteoporosis. Less commonly evaluated is men's osteoporosis knowledge. The purpose of this study is to: 1) assess the psychometric properties of the combined Facts on Osteoporosis Quiz (FOOQ) and Male Osteoporosis Knowledge Questionnaire (MOKQ) and 2) investigate the predictors of men's knowledge of osteoporosis. A sample of 1,518 men (mean age 78.6 years, S.D.=7.6; 3.6 % black), were surveyed about their knowledge of osteoporosis. Overall knowledge was poor (mean=13.2 out of a possible 26, S.D.=5.9). Rasch analysis found that the person reliability measure produced a Cronbach Alpha of 0.88. The item reliability measure produced an item to measure correlation of -0.97. The INFIT mean squares are all within the range of 0.5 to 1.5 logits indicating a good fit. One question about the effect of walking on bone health had an OUTFIT statistic out of range (4.35). Differential Item Functioning found that in general, the combined FOOQ/MOKQ preformed well across groups based on race, age, education, marital status, and residential location. Question 3, ""most people gain bone mass after 30 years of age,"" had significant and substantial difficulty differences in race, age, and education groups. To examine the predictors of men's knowledge of osteoporosis two multiple linear regressions were conducted. The first examined the relationship of demographic variables and total known risk factors on knowledge. The regression was statistically significant, F(6, 1511)=14.91, p<.001, R2=.056. Age, race, education, and total known risk factors were significant predictors of knowledge of osteoporosis. Education was the largest predictor (�=.136) with more educated men having better knowledge. The second regression explored the relationship of 18 individual risk factors on knowledge. The regression was statistically significant, F(18, 1267)=6.88, p<.001, R2=.089. Five of the risk factors (diagnosis of osteoporosis, parental fracture, participation in strength exercises, reported health, and vitamin D intake) were significant predictors. Vitamin D intake was the largest predictor (�=-0.124), such that those taking Vitamin D had better knowledge. The combined FOOQ /MOKQ is a reliable and valid measure for testing osteoporosis knowledge. A greater emphasis on educating older men about their risk for developing osteoporosis is needed