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21.
Despite increasing evidence that the fornix is important for memory, uncertainty remains about the exact nature of subsequent impairments arising from damage to this tract. This uncertainty is often created by pathology in additional brain structures. The present study involved a young man, DN, who had almost complete bilateral loss of the rostral columns of the fornix and much of the surrounding septum in the left hemisphere following the surgical removal of a cavernous angioma. Quantitative MRI analyses of structure size, normalized to intracranial volume, showed no difference in any of the additional brain regions measured, apart from those areas removed to expose the tumor. DN showed a marked, stable anterograde memory impairment that was still present 4 years postsurgery. In contrast, DN performed within normal levels on most tests of recognition memory. This sparing was most striking when given a 24-hr delay between study and test of the Warrington Recognition Memory Test. This recall/recognition dissociation provides further evidence for neuroanatomical divisions within recognition memory processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Ammonium nitrate (AN), gunpowder (GP), and an ammonium nitrate gunpowder mixture (AN/GP) were studied for impact sensitivity by four laboratories using the drop hammer apparatus. Bruceton and Neyer methods were used as experimental protocols and for data reduction. The results are presented as 50 % probability of reaction (DH50). For AN, the DH50 values are widely varied among the participants, from sensitive to completely insensitive (limit of the equipment), with no real correlation among results. GP and the AN/GP mixture exhibited much more sensitivity overall and were in some cases within statistical values extrapolated from previous studies of RDX. The variability in results for the AN data is attributed to the difficulty in determining a positive reaction event for AN, as detailed by Neyer experiments and photography during positive reactions. Variability in results for the GP and AN/GP mixtures is attributed to equipment environment and detection criteria. This work was performed by the Integrated Data Collection Analysis (IDCA) program, a multi‐laboratory effort to standardize safety testing of improvised or homemade explosives funded by the Department of Homeland Security.  相似文献   
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A new approach for determining the contributions of emission sources to concentrations of particulate matter and gases is developed using the chemical mass balance (CMB) method and the U.S. EPA's National Emission Inventory (NEI). The approach apportions combined gas-phase and condensed-phase concentrations of individual compounds as well as PM(2.5) mass. Because the NEI is used to provide source emission profiles for CMB analysis, the method generates information on the consistency of the NEI with ambient monitoring data. The method also tracks secondary species to primary source emissions, permitting a more complete accounting of the impact of aggregated source types on PM(2.5) mass concentrations. An example application is presented using four years of monitoring data collected at eight sites in the Southeastern Aerosol Research and Characterization (SEARCH) network. Including both primary and secondary species, area sources contributed 2.0-3.7 μg m(-3) (13-26%), point sources contributed 3.0-4.6 μg m(-3) (22-33%), and mobile sources contributed 1.0-6.0 μg m(-3) (9-42%) to mean PM(2.5) mass concentrations. Whereas the NEI generally accounts for the ambient concentrations of gases and particles, certain anomalies are identified, especially related to carbonaceous compounds and dust.  相似文献   
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This study compared psychopathic and nonpsychopathic rapists on static risk factors and on emotional and motivational precursors. Sixty incarcerated rapists were assessed for psychopathy with the Psychopathy Checklist—Revised (R. D. Hare, 1991), and they were classified according to the Massachusetts Treatment Center: Revised Rapist Typology, Version 3 (R. A. Knight & R. A. Prentky, l990b). Psychopathy was positively associated with past nonsexual offenses and negatively associated with age onset for criminal offending, number of sexual victims, and the intensity of negative emotions experienced before sexual offending. However, psychopathy was not related to sexual offense history, age of onset for sexual offending, or victim harm. Last, psychopaths were most likely to be classified as opportunistic and pervasively angry rapists. The findings indicate that psychopathy should be considered when developing intervention strategies for rapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In a conceptual and temporal framework, derived from research on social cognition, social interaction, and stress and coping, the authors analyze the processes through which people anticipate or detect potential stressors and act in advance to prevent them or to mute their impact (proactive coping). The framework specifies five stages in proactive coping: (1) resource accumulation, (2) recognition of potential stressors. (3) initial appraisal, (4) preliminary coping efforts, and (5) elicitation and use of feedback concerning initial efforts. The authors detail the role of individual differences, skills, and resources at each stage. They highlight the unique predictions afforded by a focus on proactive coping and the importance of understanding how people avoid and offset potential stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Proposes a theory of cognitive adaptation to threatening events. It is argued that the adjustment process centers around 3 themes: A search for meaning in the experience, an attempt to regain mastery over the event in particular and over life more generally, and an effort to restore self-esteem through self-enhancing evaluations. These themes are discussed with reference to cancer patients' coping efforts. It is maintained that successful adjustment depends, in a large part, on the ability to sustain and modify illusions that buffer not only against present threats but also against possible future setbacks. (84 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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