University of Oklahoma

About: University of Oklahoma is a education organization based out in Norman, Oklahoma, United States. It is known for research contribution in the topics: Population & Radar. The organization has 25269 authors who have published 52609 publications receiving 1821706 citations. The organization is also known as: OU & Oklahoma University.

Self-Control and Crime/Deviance: Cognitive vs. Behavioral Measures

Abstract: Using survey data, various measures of self-control, based respectively on cognitive and behavioral indicators, are compared in their ability to predict eight measures of crime/deviance. The results show that either type of measure produces supportive evidence for the theory, and the behavioral measures provide no better prediction than do the cognitive measures. Unlike cognitive type indicators, and contrary to the implications of the theory, different types of crime-analogous, imprudent behaviors are not highly interrelated, making it difficult to develop reliable behavioral measures. These results suggest that general support for self-control theory would likely not be any greater if all researchers had used behaviorally based measures, as recommended by the authors of the theory. Improving the level of prediction to the point where self-control could claim to be the master variable, as envisioned by its proponents, does not seem to rest on a shift to behaviorally based measures. Instead, improvements in the theory itself, particularly the incorporation of contingencies, appears to offer more promise.

Low‐luminosity Type II supernovae: spectroscopic and photometric evolution

Abstract: In this paper we present spectroscopic and photometric observations for four core-collapsed supernovae (SNe), namely SNe 1994N, 1999br, 1999eu and 2001dc. Together with SN 1997D, we show that they form a group of exceptionally low-luminosity events. These SNe have narrow spectral lines (indicating low expansion velocities) and low luminosities at every phase (significantly lower than those of typical core-collapsed supernovae). The very-low luminosity during the 56 Co radioactive decay tail indicates that the mass of 56 Ni ejected during the explosion is much smaller (M Ni 2-8 x 10 -3 M ○. ) than the average (M Ni 6-10 x 10 -2 M ○. ). Two supernovae of this group (SN 1999br and SN 2001dc) were discovered very close to the explosion epoch, allowing us to determine the lengths of their plateaux (100 d) as well as establishing the explosion epochs of the other, less completely observed SNe. It is likely that this group of SNe represent the extreme low-luminosity tail of a single continuous distribution of Type II plateau supernovae events. Their kinetic energy is also exceptionally low. Although an origin from low-mass progenitors has also been proposed for low-luminosity core-collapsed SNe, recent work provides evidence in favour of the high-mass progenitor scenario. The incidence of these low-luminosity SNe could be as high as 4-5 per cent of all Type II SNe.

Biodiversity and species competition regulate the resilience of microbial biofilm community.

Abstract: The relationship between biodiversity and ecosystem stability is poorly understood in microbial communities. Biofilm communities in small bioreactors called microbial electrolysis cells (MEC) contain moderate species numbers and easy tractable functional traits, thus providing an ideal platform for verifying ecological theories in microbial ecosystems. Here, we investigated the resilience of biofilm communities with a gradient of diversity, and explored the relationship between biodiversity and stability in response to a pH shock. The results showed that all bioreactors could recover to stable performance after pH disturbance, exhibiting a great resilience ability. A further analysis of microbial composition showed that the rebound of Geobacter and other exoelectrogens contributed to the resilient effectiveness, and that the presence of Methanobrevibacter might delay the functional recovery of biofilms. The microbial communities with higher diversity tended to be recovered faster, implying biofilms with high biodiversity showed better resilience in response to environmental disturbance. Network analysis revealed that the negative interactions between the two dominant genera of Geobacter and Methanobrevibacter increased when the recovery time became longer, implying the internal resource or spatial competition of key functional taxa might fundamentally impact the resilience performances of biofilm communities. This study provides new insights into our understanding of the relationship between diversity and ecosystem functioning.

Efficacy of quantified home-based exercise and supervised exercise in patients with intermittent claudication: a randomized controlled trial.

Abstract: Background—This prospective, randomized, controlled clinical trial compared changes in exercise performance and daily ambulatory activity in peripheral artery disease patients with intermittent claudication after a home-based exercise program, a supervised exercise program, and usual-care control. Methods and Results—Of the 119 patients randomized, 29 completed home-based exercise, 33 completed supervised exercise, and 30 completed usual-care control. Both exercise programs consisted of intermittent walking to nearly maximal claudication pain for 12 weeks. Patients wore a step activity monitor during each exercise session. Primary outcome measures included claudication onset time and peak walking time obtained from a treadmill exercise test; secondary outcome measures included daily ambulatory cadences measured during a 7-day monitoring period. Adherence to home-based and supervised exercise was similar (P=0.712) and exceeded 80%. Both exercise programs increased claudication onset time (P<0.001) and peak...