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Cancer Testing Technology and Saccharin

Description: A report by the Office of Technology Assessment (OTA) that, among other things, assesses "the capacity of current testing methodology to predict the carcinogenic potential of chemicals consumed by humans, with special reference to the validity of extrapolating from results of animal tests to possible human effects" (p. v). This study was done in response to the banning of the sweetener saccharin and the controversy about the testing that led to the ban.
Date: October 1977
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

An Interactive Model for Vector Borne Diseases: A Simulation for Zika in French Polynesia

Description: Post presented at Contagion 2016, a satellite meeting at the 2016 Conference on Complex Systems. This poster presents a stochastic agent-based model that simulates the transmission of ZIKA via mosquitoes in 11 islands in the French Polynesia.
Date: September 21, 2016
Creator: Gwalani, Harsha; Alshammari, Sultanah M. & Mikler, Armin R.
Partner: UNT College of Engineering

An Experimental Study of Bifurcated (Weekend and Weekday) and Unitary (Past Week) Retrospective Assessments of Sleep

Description: Discordance between weekday and weekend sleep schedules is common (Bonnet & Arand, 1995; Breslau, Roth, Rosenthal, & Andreski, 1997; Machado, Varella, & Andrade, 1998; Strauch & Meier, 1988; Tsai & Li, 2004). Brief retrospective self-report measures are essential for epidemiological research studies (Moul, Hall, Pilkonis, & Buysse, 2004), but self-reports are prone to error in recall, and the greater the variability in nightly sleep, the less reliable are retrospective reports (Babkoff, Weller, & Lavidor, 1996). More accurate self-report responses may be possible if measures prompt participants to consider variations in sleep schedules that are consistent (i.e., weekday and weekend sleep schedules). The current study experimentally examined whether Bifurcated (Weekday and Weekend) retrospective assessments of sleep are more accurate than Unitary (Past Week) assessments. Participants were randomly assigned to complete one of the two versions (Bifurcated vs. Unitary) of the Sleep Questionnaire. One hundred and thirty-one participants were included in the analyses. Results of a a series of analyses demonstrated that the Bifurcated version of the Sleep Questionnaire provided more accurate and less variable estimates of total sleep time than the Unitary version of the Sleep Questionnaire. Differences between the versions of the Sleep Questionnaire for other sleep variables were less consistent, and the increased length of the Bifurcated version of the Sleep Questionnaire may have contributed to increased missing and unusable data in this group. Overall, the findings suggest that in both research and clinical work, retrospective measures that examine weekday and weekend sleep separately may offer advantages over retrospective measures that do not differentiate between weekday and weekend sleep.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: August 2016
Creator: Sethi, Kevin J.
Partner: UNT Libraries

Sociodemographic characteristics and sexual behavior as risk factors for human papillomavirus infection in Saudi Arabia

Description: This article seeks to determine the prevalence and the sociodemographic characteristics and sexual behavior risk factors for human papillomavirus (HPV) infection in a hospital-based cohort of women in Saudi Arabia.
Date: April 3, 2016
Creator: Alhamlan, F.S.; Khayat, H.H.; Ramisetty-Mikler, Suhasini; Al-Muammar, T.A.; Tulbah, A.M.; Al-Badawi, I.A. et al.
Partner: UNT College of Information

Cognitive impairment among World Trade Center responders: Long-term implications of re-experiencing the 9/11 terrorist attacks

Description: This article examines the association between World Trade Center (WTC)-related post-traumatic stress disorder and cognitive impairment in WTC responders.
Date: August 19, 2016
Creator: Clouston, Sean A.P.; Kotov, Roman; Pietrzak, Robert H.; Luft, Benjamin J.; Gonzalez, Adam; Richards, Marcus et al.
Partner: UNT College of Arts and Sciences

Estimating Buruli Ulcer Prevalence in Southwestern Ghana

Description: Mycobacterium ulcerans is sweeping across sub-Saharan Africa, but little is known about the mode of transmission and its natural reservoirs. Since the only effective treatment is excision of the infection and surrounding tissue, early diagnosis and treatment is the only way to reduce the havoc associated with Buruli ulcer. Using data from a national case search survey conducted in Ghana during 2000 and suspected risk factors this study tests the hypothesized factors and probes the challenges of developing a spatial epidemiological regression model to explain Buruli ulcer prevalence in the southwestern region of Ghana representing 42 districts. Results suggest that prevalence is directly related to the degree of land cover classified as soil, elevation differential, and percent rural population of the area.
Date: August 2007
Creator: Denton, Curtis James
Partner: UNT Libraries

Spatially Explicit Modeling of West Nile Virus Risk Using Environmental Data

Description: West Nile virus (WNV) is an emerging infectious disease that has widespread implications for public health practitioners across the world. Within a few years of its arrival in the United States the virus had spread across the North American continent. This research focuses on the development of a spatially explicit GIS-based predictive epidemiological model based on suitable environmental factors. We examined eleven commonly mapped environmental factors using both ordinary least squares regression (OLS) and geographically weighted regression (GWR). The GWR model was utilized to ascertain the impact of environmental factors on WNV risk patterns without the confounding effects of spatial non-stationarity that exist between place and health. It identifies the important underlying environmental factors related to suitable mosquito habitat conditions to make meaningful and spatially explicit predictions. Our model represents a multi-criteria decision analysis approach to create disease risk maps under data sparse situations. The best fitting model with an adjusted R2 of 0.71 revealed a strong association between WNV infection risk and a subset of environmental risk factors including road density, stream density, and land surface temperature. This research also postulates that understanding the underlying place characteristics and population composition for the occurrence of WNV infection is important for mitigating future outbreaks. While many spatial and aspatial models have attempted to predict the risk of WNV transmission, efforts to link these factors within a GIS framework are limited. One of the major challenges for such integration is the high dimensionality and large volumes typically associated with such models and data. This research uses a spatially explicit, multivariate geovisualization framework to integrate an environmental model of mosquito habitat with human risk factors derived from socio-economic and demographic variables. Our results show that such an integrated approach facilitates the exploratory analysis of complex data and supports reasoning about the underlying spatial ...
Date: December 2015
Creator: Kala, Abhishek K.
Partner: UNT Libraries

An Investigation of the Effect of Normative Systems on an Empirical Variable

Description: This investigation is concerned, with the problem of the normative constraints upon scientific research within the broad theoretical framework of the sociology of knowledge, i.e., the contention that knowledge is functionally related to the social system. The concepts "knowledge" and "Social system" are open to wide interpretation; however, in this study knowledge refers to an empirically verifiable variable and the social system is synonomous with the normative system.
Date: December 1971
Creator: Sizemore, Mark T.
Partner: UNT Libraries

Adolescent Insomnia as a Predictor of Early Adulthood Outcomes

Description: Recent research found insomnia is a risk factor for psychiatric disorders in adults. To see if the same would be true in adolescents, the current study re-analyzed data from a national longitudinal study collected by ADDHealth that evaluated health behaviors in 4552 adolescents (mean age 14.9 years [SD 1.7]) at baseline and again 7-8 years later (n = 3489) during young adulthood. Insomnia was reported by 9.2% of the adolescents. Cross-sectionally, adolescent insomnia was associated with alcohol, cannabis, non-cannabis drugs, and tobacco use, and depression after controlling for gender and ethnicity. Prospectively, adolescent insomnia was a significant risk factor for depression diagnosis, suicidal ideation, and the use of depression and stress prescription medications in young adulthood after controlling for gender, ethnicity, and significant baseline variable. In addition, a trend was noted for suicidal attempts.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: December 2006
Creator: Roane, Brandy Michelle
Partner: UNT Libraries

Development, Implementation, and Analysis of a Contact Model for an Infectious Disease

Description: With a growing concern of an infectious diseases spreading in a population, epidemiology is becoming more important for the future of public health. In the past epidemiologist used existing data of an outbreak to help them determine how an infectious disease might spread in the future. Now with computational models, they able to analysis data produced by these models to help with prevention and intervention plans. This paper looks at the design, implementation, and analysis of a computational model based on the interactions of the population between individuals. The design of the working contact model looks closely at the SEIR model used as the foundation and the two timelines of a disease. The implementation of the contact model is reviewed while looking closely at data structures. The analysis of the experiments provide evidence this contact model can be used to help epidemiologist study the spread of an infectious disease based on the contact rate of individuals.
Date: May 2009
Creator: Thompson, Brett Morinaga
Partner: UNT Libraries

Global Stochastic Field Simulator

Description: This poster was featured at the 2013 Perot Museum of Nature and Science's 'Social Science' exhibit. It discusses the Global Stochastic Field Simulator, conceived in the summer of 2011.
Date: June 21, 2013
Creator: Mikler, Armin R.; O'Neill, Marty; Helsing, Joseph; Camp, Taylor & Indrakanti, Saratchandra
Partner: UNT College of Engineering

The Influence of Social Network Graph Structure on Disease Dynamics in a Simulated Environment

Description: The fight against epidemics/pandemics is one of man versus nature. Technological advances have not only improved existing methods for monitoring and controlling disease outbreaks, but have also provided new means for investigation, such as through modeling and simulation. This dissertation explores the relationship between social structure and disease dynamics. Social structures are modeled as graphs, and outbreaks are simulated based on a well-recognized standard, the susceptible-infectious-removed (SIR) paradigm. Two independent, but related, studies are presented. The first involves measuring the severity of outbreaks as social network parameters are altered. The second study investigates the efficacy of various vaccination policies based on social structure. Three disease-related centrality measures are introduced, contact, transmission, and spread centrality, which are related to previously established centrality measures degree, betweenness, and closeness, respectively. The results of experiments presented in this dissertation indicate that reducing the neighborhood size along with outside-of-neighborhood contacts diminishes the severity of disease outbreaks. Vaccination strategies can effectively reduce these parameters. Additionally, vaccination policies that target individuals with high centrality are generally shown to be slightly more effective than a random vaccination policy. These results combined with past and future studies will assist public health officials in their effort to minimize the effects of inevitable disease epidemics/pandemics.
Date: December 2010
Creator: Johnson, Tina V.
Partner: UNT Libraries

Optimizing Non-pharmaceutical Interventions Using Multi-coaffiliation Networks

Description: Computational modeling is of fundamental significance in mapping possible disease spread, and designing strategies for its mitigation. Conventional contact networks implement the simulation of interactions as random occurrences, presenting public health bodies with a difficult trade off between a realistic model granularity and robust design of intervention strategies. Recently, researchers have been investigating the use of agent-based models (ABMs) to embrace the complexity of real world interactions. At the same time, theoretical approaches provide epidemiologists with general optimization models in which demographics are intrinsically simplified. The emerging study of affiliation networks and co-affiliation networks provide an alternative to such trade off. Co-affiliation networks maintain the realism innate to ABMs while reducing the complexity of contact networks into distinctively smaller k-partite graphs, were each partition represent a dimension of the social model. This dissertation studies the optimization of intervention strategies for infectious diseases, mainly distributed in school systems. First, concepts of synthetic populations and affiliation networks are extended to propose a modified algorithm for the synthetic reconstruction of populations. Second, the definition of multi-coaffiliation networks is presented as the main social model in which risk is quantified and evaluated, thereby obtaining vulnerability indications for each school in the system. Finally, maximization of the mitigation coverage and minimization of the overall cost of intervention strategies are proposed and compared, based on centrality measures.
Date: May 2013
Creator: Loza, Olivia G.
Partner: UNT Libraries

Simulating the Spread of Infectious Diseases in Heterogeneous Populations with Diverse Interactions Characteristics

Description: The spread of infectious diseases has been a public concern throughout human history. Historic recorded data has reported the severity of infectious disease epidemics in different ages. Ancient Greek physician Hippocrates was the first to analyze the correlation between diseases and their environment. Nowadays, health authorities are in charge of planning strategies that guarantee the welfare of citizens. The simulation of contagion scenarios contributes to the understanding of the epidemic behavior of diseases. Computational models facilitate the study of epidemics by integrating disease and population data to the simulation. The use of detailed demographic and geographic characteristics allows researchers to construct complex models that better resemble reality and the integration of these attributes permits us to understand the rules of interaction. The interaction of individuals with similar characteristics forms synthetic structures that depict clusters of interaction. The synthetic environments facilitate the study of the spread of infectious diseases in diverse scenarios. The characteristics of the population and the disease concurrently affect the local and global epidemic progression. Every cluster’ epidemic behavior constitutes the global epidemic for a clustered population. By understanding the correlation between structured populations and the spread of a disease, current dissertation research makes possible to identify risk groups of specific characteristics and devise containment strategies that facilitate health authorities to improve mitigation strategies.
Date: December 2013
Creator: Gomez-Lopez, Iris Nelly
Partner: UNT Libraries