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31.
Prior research has demonstrated deficits in defensive reactivity (indexed by potentiation of the startle blink reflex) in psychopathic individuals. However, the basis of this association remains unclear, as diagnostic criteria for psychopathy encompass two distinct phenotypic components that may reflect differing neurobiological mechanisms—an affective–interpersonal component and an antisocial deviance component. Likewise, the role of defensive response deficits in antisocial personality disorder (APD), a related but distinct syndrome, remains to be clarified. In the current study, the authors examined affective priming deficits in relation to factors of psychopathy and symptoms of APD using startle reflex methods in 108 adult male prisoners. Deficits in blink reflex potentiation during aversive picture viewing were found in relation to the affective–interpersonal (Factor 1) component of psychopathy, and to a lesser extent in relation to the antisocial deviance (Factor 2) component of psychopathy and symptoms of APD—but only as a function of their overlap with affective–interpersonal features of psychopathy. These findings provide clear evidence that deficits in defensive reactivity are linked specifically to the affective–interpersonal features of psychopathy and not to the antisocial deviance features represented most strongly in APD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Contribution to the topic with the case of a woman, 24, admitted in our ENT Department for exam and treatment of multiple right sided adenopathies of the neck. The histopathological study was consistent with diagnosis of Kikuchi's necrotizing lymphadenitis. This is a new clinicopathologic entity first described, 1972, by Kikuchi, of unknown etiology, an a picture characterized for painful cervical lymphadenitis presented in young women and healing spontaneously after 2-3 months course. We want to emphasize in this paper the scarcity of cases published and the difficulties arising when dealing with the differential diagnosis with lympho-proliferative malignancies as well.  相似文献   
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34.
We have designed a large helium dewar as part of an experiment to investigate gravitational radiation. Two such dewars have been constructed. Our use requires a nonmagnetic dewar to cool an aluminium antenna of approximately 5000 kg to below helium temperatures and to keep the antenna in a stable low temperature environment for extended time. This requires a low temperature volume of 1.5 m inner diameter and 3.1 m length and a cooling system capable of efficiently removing the room temperature enthalpy of 8.5 × 108 J. Our solution to this problem is of wider application than simply gravity wave detection so we have discussed the design philosophy in some detail. As constructed, the apparatus uses less than 1 l of helium per hour when cold.  相似文献   
35.
Using a classical conditioning technique, this study investigated whether nonconscious associative learning could be indexed by event-related brain activity (ERP). There were three phases. In a preconditioning baseline phase, pleasant and unpleasant facial schematics were presented in awareness (suprathreshold). A conditioning phase followed, in which stimuli were presented outside awareness (subthreshold, via energy masking), with an unpleasant face (CS+) linked to an aversive shock and a pleasant face (CS-) not linked to a shock. The third, postconditioning phase, involved stimulus presentations in awareness (suprathreshold). Evidence for acquisition of a conditional response was sought by comparing suprathreshold pre- and postconditioning phases, as well as in the subthreshold conditioning phase itself. For the pre-postconditioning phase analyses, significant ERP component differences differentiating CS+ and CS- were observed for N1, P2, and especially P3. For the conditioning phase, significant differences were observed in the 100-400 ms. post-stimulus region reflecting a CS+ processing negativity. Brain activity does indeed index the acquisition of a conditional response to subthreshold stimuli. Associative learning can occur outside awareness.  相似文献   
36.
    
The presented paper proposes a novel method of observer design. A new two-layer observer structure is introduced. The first layer consists of multiple high-gain observers. The latter is built to connect the first layer observers into single one. As the new contribution, the new mapping is defined between an unknown state and measurable outputs allowing to explore new estimation schema. Hence, the proposed method enhances the estimation process for linear and nonlinear systems. Furthermore, it is shown that the introduced observation scheme improves the transients. Illustrative examples are calculated to show the properties of the new observation method.  相似文献   
37.
Noninvasive methods for efficient drug delivery to the brain is an unmet need. Molecular access to the brain is regulated by the blood–brain barrier (BBB) established by the endothelial cells of brain vessels. Passive diffusion is one of the main mechanisms that organic compounds use to travel through these endothelial cells. This passage across the BBB is determined mainly by certain physicochemical properties of the molecule such as lipophilicity, size, and the presence of hydrogen bond donors and acceptors. One emerging strategy to facilitate the passage of organic compounds across the BBB is the use of peptide shuttles. 1 In using this approach the permeability in front the BBB is, clearly, determined by the combined physicochemical properties of both the cargo and the shuttle. Herein we report the synthesis of a series of variations of one of the more efficient peptide shuttles, (N‐MePhe)n. These include diverse structural features such as various backbone stereochemistries or the presence of non‐natural amino acids, including halogenated residues. In several cases, we assessed the BBB permeability of both the shuttles alone and linked to a few cargos. Our results show how factors such as stereochemistry or halogen content influences the passage across the BBB and, more importantly, opens the way to a strategy of peptide shuttles ‘à la carte′, in which a particular fine‐tuned shuttle is used for each specific cargo.  相似文献   
38.
Background: In the past few decades, numerous policies, including those that lower legal blood alcohol concentration limits, have been enacted to reduce alcohol-impaired driving. In the US, 41 states and the District of Columbia have enacted 0.08 per se laws, which specify that if a driver’s BAC is at or above 0.08, a violation has occurred even if the driver does not show signs of intoxication. Objective: We examined effects of lowering the blood alcohol concentration limit to 0.08 per se on fatal traffic crashes in 18 states and the District of Columbia, and whether effects of the law varied by state or by baseline rates of fatal traffic crashes. Method: Data on fatal traffic crashes were obtained from the Fatality Analysis Reporting System, including all states that enacted 0.08 per se prior to 2001 in the contiguous United States. Effects of the 0.08 law were examined in each state separately, and the overall effect across states was examined using a mixed-model Poisson regression on single-vehicle-nighttime fatal traffic crashes. Results: State-specific analyses showed that fatal traffic crashes significantly decreased in three of the 19 states following the introduction of the 0.08 law, prior to adjusting for potential confounders. The mixed-model regression showed a statistically significant 5.2% reduction in single-vehicle-nighttime fatal traffic crashes associated with the 0.08 law across all states, after adjusting for administrative license revocation, the number of Friday and Saturday nights in a month, and trends in all other types of fatal traffic crashes. Findings indicate that the effect of the 0.08 law does not vary significantly by state or baseline rate of fatal traffic crashes in a state, and no significant statistical interaction exists between 0.08 and administrative license revocation policy effects.  相似文献   
39.
This study used experimental methodology to investigate the differential impact of various levels of sexual victimization on women's perceptions of risk and evaluative judgments of sexual assault within a dating interaction. Single- and multiple-incident victims were compared with nonvictims. Results supported the hypothesis that revictimized women would exhibit longer latencies than either single incident victims or nonvictims in signaling that an audiotaped date rape should be halted. Revictimized women with greater posttraumatic stress disorder (PTSD) symptoms, arousal symptoms in particular, exhibited latencies similar to those of nonvictims, whereas revictimized women with lower levels of PTSD symptoms had significantly longer latencies. Dissociative symptoms were not related to latency These findings suggest that PTSD-related arousal symptoms may serve a buffering effect, increasing sensitivity to threat cues that portend a sexually coercive interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
The oil price instability and the measures taken to reduce the increase in greenhouse gas emissions are the main factors promoting the development and use of environmentally friendly energies. From an energy efficiency point of view, biofuels constitute a renewable energy source and its use helps to reduce energy dependency on fossil fuels. The most used biofuels for transport worldwide are biodiesel (BD) and bioethanol. However, there are other options such as straight vegetable oil (SVO).SVO can be small-scale produced in local cooperatives through pressing, filtering and conditioning processes which are much simpler than the ones required for BD production. In this study a comparative life cycle assessment (LCA) of two biofuels obtained from Spanish rapeseed, namely small-scale SVO and large-scale BD, is performed. The LCA methodology allows the two biofuels’ production and their rate of consumption in a vehicle (a truck) to be compared. In this manner, it is possible to assess which is environmentally advantageous: to use SVO directly as biofuel or to convert it to BD. Moreover, LCA is used in the study to calculate the energy return on investment index (EROI) and an energy conversion ratio to evaluate which biofuel is more energy efficient.The obtained results show the environmental benefits of using SVO instead of BD by analyzing representative impact categories defined by the CML and EDIP methods. A sensitivity analysis has also been conducted. EROI indexes for SVO and BD production show a clear preference for SVO as compared to BD.  相似文献   
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