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Objectives: Neuropsychological studies of posttraumatic stress disorder (PTSD) have revealed deficits in attention/working memory, processing speed, executive functioning, and retrospective memory. However, little is known about prospective memory (PM) in PTSD, a clinically relevant aspect of episodic memory that supports the encoding and retrieval of intentions for future actions. Methods: Here we examined PM performance in 40 veterans with PTSD compared to 38 trauma comparison (TC) veterans who were exposed to combat but did not develop PTSD. All participants were administered the Memory for Intentions Test (MIST; Raskin, Buckheit, & Sherrod, 2010), a standardized and validated measure of PM, alongside a comprehensive neurocognitive battery, structured diagnostic interviews for psychiatric conditions, and behavioral questionnaires. Results: Veterans with PTSD performed moderately lower than TC on time-based PM, with errors primarily characterized as PM failure errors (i.e., omissions). However, groups did not differ in event-based PM, ongoing task performance, or post-test recognition of PM intentions for each trial. Lower time-based PM performance was specifically related to hyperarousal symptoms of PTSD. Time-based-performance was also associated with neuropsychological measures of retrospective memory and executive functions in the PTSD group. Nevertheless, PTSD was significantly associated with poorer PM above and beyond age and performance in retrospective memory and executive functions. Discussion: Results provide initial evidence of PM dysfunction in PTSD, especially in strategic monitoring during time-based PM tasks. Findings have potential implications for everyday functioning and health behaviors in persons with PTSD, and deserve replication and future study. (JINS, 2016, 22, 724–734)
Objectives: Numerous studies have shown that individuals with posttraumatic stress disorder (PTSD) display reduced performances on neuropsychological tests, although most prior research has not adequately accounted for comorbidities or performance validity concerns that are common in this population and could partially account for the observed neurocognitive findings. Moreover, few studies have examined the functional implications of neuropsychological results in PTSD. Methods: We examined neuropsychological functioning in 44 veterans with PTSD and 40 veteran trauma comparison (TC) participants with combat exposure and no PTSD. Results: After excluding four veterans with PTSD for performance validity concerns, multivariate analyses of variance by neurocognitive domain revealed significantly worse performance by the PTSD group in the domains of speed of information processing (p=.035) and executive functions (p=.017), but no group differences in attention/working memory, verbal/language functioning, visuoconstruction, or episodic memory. Group differences by PTSD status were still present after covarying for depression, a history of head injuries, and substance use disorders. Executive functioning performance was associated with poorer self-reported occupational functioning and physical health-related quality of life, while speed of information processing performance was associated with poorer physical health-related quality of life. Discussion: These results are generally consistent with a fronto-limbic conceptualization of PTSD-associated neuropsychological dysfunction and show that cognitive functioning may be associated with critical functional outcomes. Taken together, results suggest that consideration of neurocognitive functioning may enhance the clinical management of individuals with PTSD. (JINS, 2016, 22, 399–411)
On January 24, 1913, the trustees of the Dalcho School, a segregated, all-white public school in Dillon County, South Carolina, summarily dismissed Dudley, Eugene, and Herbert Kirby, ages ten, twelve, and fourteen, respectively. According to testimony offered in a subsequent hearing, the boys had “always properly behaved,” were “good pupils,” and “never …exercise[d] any bad influence in school.” Moreover, the boys’ overwhelmingly white ancestry, in the words of the South Carolina Supreme Court, technically “entitled [them] to be classified as white,” according to state law. Nevertheless, because local whites believed that the Kirbys were “not of pure Caucasian blood,” and that therefore their removal was in the segregated school's best interest, the court, in Tucker v. Blease (1914), upheld their expulsion.
The Petexbatun Regional Cave Survey (PRCS) is the first large cave study to be undertaken as part of a major archaeological expedition. The survey's primary objective was assessing the extent to which surface architecture at Dos Pilas was configured by features in the sacred landscape. All three of the major architectural complexes at the site had a direct relation to caves, and a number of important secondary buildings and even residential units were deliberately laid out to incorporate caves. Excavation revealed evidence of Preclassic utilization of all of the major caves, indicating that their status as sacred landmarks had been established long before the eighth century florescence of the site. The importance of the caves in site configuration was mirrored in the artifact assemblage. Despite the survey's much smaller size, the cave investigations recovered 20–50% more of the overall assemblage at Dos Pilas in an array of artifact categories. A review of the archaeological literature suggests that the importance ascribed to caves at Dos Pilas in both site configuration and local economy can be found elsewhere and probably reflects a much wider pattern of utilization.
Saproxylic insect assemblages inhabiting dead wood in Canadian forests are highly diverse and variable but quite poorly understood. Adequate assessment of these assemblages poses significant challenges with respect to sampling, taxonomy, and analysis. Their assessment is nonetheless critical to attaining the broad goals of sustainable forest management because such species are disproportionately threatened elsewhere by the reductions in dead wood generally associated with commercial exploitation of northern forests. The composition of the saproxylic fauna is influenced by many factors, including tree species, degree of decay, stand age, and cause of tree death. Wildfire and forest harvesting have differential impacts on saproxylic insect assemblages and on their recovery in postdisturbance stands. Exploration of saproxylic insect responses to variable retention harvesting and experimental burns is contributing to the development of prescriptions for conserving saproxylic insects in boreal forests. Understanding of processes that determine diversity patterns and responses of saproxylic insects would benefit from increased attention to natural history. Such work should aim to provide a habitat-classification system for dead wood to better identify habitats (and associated species) at risk as a result of forest management. This tool could also be used to improve strategies to better maintain saproxylic organisms and their central nutrient-cycling functions in managed forests.
Herbicide resistance is the heritable ability of a weed biotype or population to survive a herbicide application that would effectively kill a susceptible population of the weed. In the U.K. the most widespread and financially important herbicide-resistant weed is blackgrass. Investigations to elucidate the molecular mechanisms conferring herbicide resistance to blackgrass populations have been ongoing for two decades. Although the identification of target site–resistant populations has proved to be relatively straightforward (using, for example, target site assays in vitro), the study and understanding of resistance mechanisms involved in enhanced metabolism has proven to be more problematic. Research has focused on the cytochrome P450 monooxygenase and glutathione S-transferase (GST) enzyme families, both of which have been shown to be important in herbicide metabolism in many weed and crop species. GST activity and abundance are greater in a selection of herbicide-resistant blackgrass biotypes, and herbicide treatment of field populations of blackgrass results in the survival of the proportion of population possessing the greatest GST activity and abundance. In addition, GST activity in the field increases between winter and spring, and this coincides with reduced efficacy of important blackgrass herbicides. GST activities within field populations of blackgrass are highly varied, and this plasticity is discussed in relation to the development of resistant populations in field situations. This article describes research results in blackgrass and compares them with GST studies in other weed species as well as with other mechanisms for enhanced metabolism-based resistance.
Vertical posture has been studied only in the scutellid sand dollar Dendraster excentricus although it has been reported in another Dendraster species and two species of laganid sand-dollars. The vertical posture has been associated with the posterior eccentric position of the apical system and petals of the test. We have discovered the scutellid sand dollar Encope michelini, which shows no eccentricity of the apical system and petals, also has the vertical posture in the population studied. Absence of eccentricity of the apical system and petals in living and fossil sand-dollars does not indicate absence of the vertical posture.
The presence of angiotensin I-converting enzyme-like activity (ACELA) was investigated in whole
body homogenates of Branchiostoma lanceolatum using a highly sensitive fluorimetric assay. The
measured enzyme activity was inhibited by the two angiotensin converting enzyme inhibitors,
captopril and enalapril, suggesting a biochemical pathway that could generate the angiotensins
observed in the central nervous system of amphioxus.
A shadow of a subset A of ℝn is the image of A
under a projection onto a hyperplane. Let C be a closed nonconvex set in ℝn
such that the closures of all its shadows are convex. If, moreover, there are n
independent directions such that the closures of the shadows of C in those directions are proper subsets
of the respective hyperplanes then it is shown that C contains a copy of ℝn−2.
Also for every closed convex set B ‘minimal imitations’ C of B are constructed,
that is, closed subsets C of B that have the
same shadows as B and that are minimal with respect to dimension.
Radiocarbon age determinations are presented on three hieroglyphic texts from Naj Tunich cave in Guatemala containing Maya calendar dates. The ages obtained are on average 110–140 years older than the calendar dates. Several possible reasons are discussed for this discrepancy: one that is applicable to all radiocarbon dates on charcoal, one that applies to rock paintings, and one that is specific for the tropics. Possible problems with the ages ascribed to the Maya calendar dates are also discussed. Even with the potential problems that may exist, these dates still fall within 110–140 years of the ascribed calendar dates. Caution is urged in the interpretation of dates on charcoal pigments from rock paintings; consideration of the “old wood” and “old charcoal” factors is important.
Preliminary work in assessing the competency of trainees attending a cognitive behaviour therapy course is presented. Inter-rater reliability of the Cognitive Therapy Scale to assess competency in therapy is considered satisfactory at the overall competency level. Item reliabilities are promising. Although the power of this pilot design is weak, the competency scale showed a trend towards improvement over the course of training.