University of North Texas

About: University of North Texas is a education organization based out in Denton, Texas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 11866 authors who have published 26984 publications receiving 705376 citations. The organization is also known as: Fight, North Texas & UNT.

Using methods that matter: the impact of reflection, dialogue, and voice.

Abstract: In recent years, the field of community psychology has given considerable attention to how research and evaluation methods should be designed to support our goals of empowerment and social justice. Yet, as a field, we have given much less attention to whether the use of our methods actually achieves or supports our empowerment agenda. With the primary purpose of beginning to establish the norm of reporting on the impacts of our methods, this paper reports on the findings from interviews of 16 youth and adults who had participated in one participatory evaluation method (Photovoice). Two specific questions were examined: (1) What is the impact of participating in a Photovoice effort; and (2) How does the method of Photovoice foster these impacts? Overall, participants noted that they were significantly affected by their experiences as photographers and through their dialogue with neighbors during Photovoice group sessions. Impacts ranged from an increased sense of control over their own lives to the emergence of the kinds of awareness, relationships, and efficacy supportive of participants becoming community change agents. According to participants, Photovoice fostered these changes by (a) empowering them as experts on their lives and community, (b) fostering deep reflection, and (c) creating a context safe for exploring diverse perspectives. The implications of these findings for the science and practice of community psychology are discussed.

Effect of microstructure of nitrogen-doped graphene on oxygen reduction activity in fuel cells.

Abstract: The development of fuel cells as clean-energy technologies is largely limited by the prohibitive cost of the noble-metal catalysts needed for catalyzing the oxygen reduction reaction (ORR) in fuel cells. A fundamental understanding of catalyst design principle that links material structures to the catalytic activity can accelerate the search for highly active and abundant nonmetal catalysts to replace platinum. Here, we present a first-principles study of ORR on nitrogen-doped graphene in acidic environment. We demonstrate that the ORR activity primarily correlates to charge and spin densities of the graphene. The nitrogen doping and defects introduce high positive spin and/or charge densities that facilitate the ORR on graphene surface. The identified active sites are closely related to doping cluster size and dopant–defect interactions. Generally speaking, a large doping cluster size (number of N atoms >2) reduces the number of catalytic active sites per N atom. In combination with N clustering, Stone-W...

The epidemiology of serious eye injuries from the United States Eye Injury Registry.

Abstract: · Background: Trauma remains a major problem throughout the world. The prognosis of severe eye injuries is commonly bleak. This paper focuses on the epidemiology of eye trauma, the role of ocular epidemiology, and identification and reduction of risk factors. · Methods: An analysis of the first 8,952 patients reported with severe eye injuries, defined as those eye injuries resulting in permanent and significant (measurable and observable on routine eye examination) structural and/or functional changes to the eye, from the United States Eye Injury Registry as of 31 July 1998. · Results: The age of patients entered was from the 1st year of life to 103 years. Fifty-eight percent of those injured were less than 30 years of age. The male to female ratio was 4.6:1, reaching 7.4:1 in the fourth decade of life. Almost half of the injuries involved the retina, and 77% of the injured eyes required one or more surgical procedures, including a large proportion which have undergone vitreoretinal surgical procedures. · Conclusion: Injuries remain the most serious public health problem facing developed nations. Yet, a persistent inadequacy exists both in the standardized documentation of eye injuries and in their treatment. With appropriate surgical and medical intervention, a majority of the reported injured eyes recovered functional levels of visual acuity. It appears that glasses, including prescription glasses and even non-prescription sunglasses, can offer measurable protection which results in a lower incidence of severe eye injuries to those wearing glasses.

New insights into central cardiovascular control during exercise in humans: a central command update.

Abstract: The autonomic adjustments to exercise are mediated by central signals from the higher brain (central command) and by a peripheral reflex arising from working skeletal muscle (exercise pressor reflex), with further modulation provided by the arterial baroreflex. Although it is clear that central command, the exercise pressor reflex and the arterial baroreflex are all requisite for eliciting appropriate cardiovascular adjustments to exercise, this review will be limited primarily to discussion of central command. Central modulation of the cardiovascular system via descending signals from higher brain centres has been well recognized for over a century, yet the specific regions of the human brain involved in this exercise-related response have remained speculative. Brain mapping studies during exercise as well as non-exercise conditions have provided information towards establishing the cerebral cortical structures in the human brain specifically involved in cardiovascular control. The purpose of this review is to provide an update of current concepts on central command in humans, with a particular emphasis on the regions of the brain identified to alter autonomic outflow and result in cardiovascular adjustments.

Conformal Fractals: Ergodic Theory Methods

Abstract: Introduction Basic examples and definitions 1. Measure preserving endomorphisms 2. Compact metric spaces 3. Distance expanding maps 4. Thermodynamical formalism 5. Expanding repellers in manifolds and in the Riemann sphere, preliminaries 6. Cantor repellers in the line, Sullivan's scaling function, application in Feigenbaum universality 7. Fractal dimensions 8. Conformal expanding repellers 9. Sullivan's classification of conformal expanding repellers 10. Holomorphic maps with invariant probability measures of positive Lyapunov exponent 11. Conformal measures References Index.