DePaul University

About: DePaul University is a education organization based out in Chicago, Illinois, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 5658 authors who have published 11562 publications receiving 295257 citations.

Perceptions of Risk and the Buffering Hypothesis: The Role of Just World Beliefs and Right-Wing Authoritarianism

Abstract: Although perceptions of risk have been studied extensively by both social and cognitive psychologists, relatively little work has focused on individual differences in these perceptions. Across two studies, the authors examined the relationship of perceived risk to just world beliefs (BJW) and right-wing authoritarianism (RWA). Both studies showed that these two variables have interactive effects on perceived risk across a wide variety of different types of threats (e.g., getting hijacked, contracting AIDS). Among high authoritarians, participants felt much less at risk if they believed in a just world than if they did not. Among low authoritarians, however, BJW and perceived risk were unrelated. Results are conceptualized in terms of a buffering hypothesis, which suggests that the extent to which self-protective variables (such as BJW) mediate risk are most pronounced among persons who view the world in threatening terms (i.e., high authoritarians). Implication of these findings for previous models of ris...

Performance Modeling and Analysis of Network Firewalls

Abstract: Network firewalls act as the first line of defense against unwanted and malicious traffic targeting Internet servers. Predicting the overall firewall performance is crucial to network security engineers and designers in assessing the effectiveness and resiliency of network firewalls against DDoS (Distributed Denial of Service) attacks as those commonly launched by today's Botnets. In this paper, we present an analytical queueing model based on the embedded Markov chain to study and analyze the performance of rule-based firewalls when subjected to normal traffic flows as well as DoS attack flows targeting different rule positions. We derive equations for key features and performance measures of engineering and design significance. These features and measures include throughput, packet loss, packet delay, and firewall's CPU utilization. In addition, we verify and validate our analytical model using simulation and real experimental measurements.

Shock-synthesized hexagonal diamonds in Younger Dryas boundary sediments

Abstract: The long-standing controversy regarding the late Pleistocene megafaunal extinctions in North America has been invigorated by a hypothesis implicating a cosmic impact at the Ållerod-Younger Dryas boundary or YDB (≈12,900 ± 100 cal BP or 10,900 ± 100 14C years). Abrupt ecosystem disruption caused by this event may have triggered the megafaunal extinctions, along with reductions in other animal populations, including humans. The hypothesis remains controversial due to absence of shocked minerals, tektites, and impact craters. Here, we report the presence of shock-synthesized hexagonal nanodiamonds (lonsdaleite) in YDB sediments dating to ≈12,950 ± 50 cal BP at Arlington Canyon, Santa Rosa Island, California. Lonsdaleite is known on Earth only in meteorites and impact craters, and its presence strongly supports a cosmic impact event, further strengthened by its co-occurrence with other nanometer-sized diamond polymorphs (n-diamonds and cubics). These shock-synthesized diamonds are also associated with proxies indicating major biomass burning (charcoal, carbon spherules, and soot). This biomass burning at the Younger Dryas (YD) onset is regional in extent, based on evidence from adjacent Santa Barbara Basin and coeval with broader continent-wide biomass burning. Biomass burning also coincides with abrupt sediment mass wasting and ecological disruption and the last known occurrence of pygmy mammoths (Mammuthus exilis) on the Channel Islands, correlating with broader animal extinctions throughout North America. The only previously known co-occurrence of nanodiamonds, soot, and extinction is the Cretaceous-Tertiary (K/T) impact layer. These data are consistent with abrupt ecosystem change and megafaunal extinction possibly triggered by a cosmic impact over North America at ≈12,900 ± 100 cal BP.

Premarital Sexual Standards and Sociosexuality: Gender, Ethnicity, and Cohort Differences

Abstract: In this article, we present results from a “cohort-longitudinal” analysis of sexual attitudes and behaviors based on a large sample of young adults (N = 7,777) obtained from a university setting over a 23-year period. We investigated gender, ethnicity, and cohort differences in sexual permissiveness, endorsement of the double standard, and sociosexuality. Compared to women, men had more permissive attitudes, particularly about sex in casual relationships, endorsed the double standard to a greater degree, and had a more unrestricted sociosexuality. Black men were generally more permissive than White, Hispanic, and Asian men, whereas ethnic differences were not found among women. Participants from the 1995–1999 cohort were slightly less permissive than those from the 1990–1994 and 2005–2012 cohorts. Although prior meta-analytic studies (e.g., Petersen & Hyde, 2010) found reduced gender differences in sexuality over time, our cohort analyses suggest that gender differences in sexual permissiveness have not changed over the past two decades among college students.

Do Envious CEOs Cause Merger Waves

Abstract: We develop a theory which shows that merger waves can arise even when the shocks that precipitated the initial mergers in the wave are idiosyncratic. The analysis predicts that the earlier acquisitions produce higher bidder returns, involve smaller targets, and result in higher compensation gains for the acquirer’s top management team than the later acquisitions in the wave. We find strong empirical support for these predictions. The model also generates additional predictions, some of which remain to be tested. (JEL G34)