30 research outputs found
The Avian Hippocampal Declarative Memory System
Across Mammalia, memory has long been dissociated into multiple component systems specialized to process specific facets of experience. Among these segregated systems, declarative memory is processed by the hippocampus and surrounding structures, which have collectively been referred to as the hippocampal declarative memory system (HDMS). The HDMS, in turn, can be further divided into parallel streams dedicated to the processing of spatial versus object identity based information, commonly discussed as the âwhatâ and âwhereâ streams. While we know that the organization of the HDMS is conserved in humans, nonhuman primates, and rats, evidence outside Mammalia is lacking. Here HDMS homology is tested in Aves, a class known to have sophisticated memory abilities. This dissertation first adapts testing methods well established for dissociating spatial and object recognition in mammals and validates them in multiple avian species (Chapter 2). These methods are then applied to birds undergoing selective lesions along either the mediolateral (Chapter 3) or rostrocaudal (Chapter 4) extent of the HDMS. These data then permit an update of the known functions of the sub-regions of the avian HDMS (Chapter 5). In summary, these data suggest that most of the key features of the mammalian HDMS, including the existence of anatomically separated hierarchical processing streams for object and spatial information, as well as eventual convergence of this information in the hippocampal formation, is conserved across at least these two classes. Given the great survival value of the ability to identify the âwhatsâ and âwheresâ within an environment, this homology may not be surprising. In fact, the HDMS may be conserved across much of the animal kingdom
Their Day in Court: Assessing Guilty Plea Rates Among Terrorists
Individuals who are charged for traditional crimes are substantially more likely to plead guilty than individuals who are charged under the same statutes but who are officially involved in terrorism (Smith & Damphousse, 1998). Relying on a structuralâcontextual theory framework, a quantitative analysis not only confirmed that terrorists plead guilty more often than traditional offenders but that the defendantâs age and number of counts in the indictment are important predictors. Directions for future research are suggested.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Orally available Mn porphyrins with superoxide dismutase and catalase activities
Superoxide dismutase/catalase mimetics, such as salen Mn complexes and certain metalloporphyrins, catalytically neutralize reactive oxygen and nitrogen species, which have been implicated in the pathogenesis of many serious diseases. Both classes of mimetic are protective in animal models of oxidative stress. However, only AEOL11207 and EUK-418, two uncharged Mn porphyrins, have been shown to be orally bioavailable. In this study, EUK-418 and several new analogs (the EUK-400 series) were synthesized and shown to exhibit superoxide dismutase, catalase, and peroxidase activities in vitro. Some also protected PC12 cells against staurosporine-induced cell death. All EUK-400 compounds were stable in simulated gastric fluid, and most were substantially more lipophilic than the salen Mn complexes EUK-189 and EUK-207, which lack oral activity. Pharmacokinetics studies demonstrate the presence of all EUK-400 series compounds in the plasma of rats after oral administration. These EUK-400 series compounds are potential oral therapeutic agents for cellular damage caused by oxidative stress
Punishing Terrorists: A Re-Examination of U.S. Federal Sentencing in the Postguidelines Era
The empirical literature on the theory and practice of sentencing politically motivated offenders such as terrorists in U.S. federal courts is limited. Thus, we know relatively little about the dealings between terrorist offenders and the criminal justice system or how these interactions may be influenced by changes in American legal or political context. This study summarizes previous findings relative to sentencing disparity among terrorists and nonterrorists in U.S. federal courts prior to the imposition of the U.S. Sentencing Guidelines. We then identify events occurring after the advent of the guidelines, including the early acts of terrorism on American soil. We evaluate the sentencing of terrorists versus nonterrorists following the confluence imposition of the guidelines and these events. We determine whether and how the sentencing disparity between terrorist and nonterrorist has changed since the implementation of the U.S. Sentencing Guidelines and the terrorist events of the early 1990s. Based on our findings, we put forth suggestions as to the possible ways these conditions may have affected sentencing outcomes.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Altered pattern separation in Goto-Kakizaki rats
Type 2 diabetes mellitus has steadily increased in prevalence over the past five decades. Among the health risks associated with this disorder are cognitive decline and are increased risk of developing dementia. To further investigate the link between diabetes and cognition, here we test memory performance and hippocampal function in the Goto-Kakizaki (GK) rat, a robust model of diabetes. Relative to age-matched Wistar rats, GK rats show impairments in a conjunctive memory task that requires discriminating objects not only on the basis of their physical characteristics, but also on the basis of where and when they were last seen. Concomitant to these deficits are changes in the pattern of expression of Egr1 (an immediate-early gene critical for memory) in dentate gyrus granule cells, consistent with dentate hypoactivity leading to unstable hippocampal representations. These data support the hypothesis that diabetes confers a phenotype of accelerated senescence on the hippocampus, and help to link this disorder with changes in hippocampal circuits