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221.
C Garcia P Philippot B Lacarelle M Valli B Rimé B Bruguerolle O Blin 《Canadian Metallurgical Quarterly》1997,11(5):466-475
We studied the effects of lorazepam, a benzodiazepine, on differentiated emotions in healthy volunteers. In order to induce differentiated emotions, film excerpts were selected on the basis of the type of emotion they induced (fear, anger and for affective tone neutral film). For 6 days (D1 to D6), ten healthy volunteers received lorazepam (1 mg bid) or placebo in a randomized cross-over double-blind trial. During each treatment period, emotional induction occurred on D4, D5 and D6. One film excerpt (fear, anger or neutral) was presented each morning after relaxation. Evaluation was performed before and after each emotional induction and included questionnaires (Differential Emotions Scale and physical activation visual analog scales), and neurophysiological parameters (systolic and diastolic blood pressure, heart rate and norepinephrine levels). Globally, the film excerpts induced the predicted emotions. An analysis of variance was undertaken and revealed a significant effect of lorazepam versus placebo. On the Differential Emotions Scale and during fear induction, lorazepam induced a significantly higher increase in fear, anxiety and disgust emotions than placebo, whereas no effect was observed after anger induction. Lorazepam also induced a significantly higher increase in diastolic and systolic blood pressure with no change in heart rate, and physical activation items ("tears" and "faster breathing") without no significant change in norepinephrine. In conclusion, our results are consistent with an overall increase in emotional reactivity with lorazepam (1 mg bid) as compared to placebo. The pertinence of film-induced differentiated emotions has to be confirmed for clinical pharmacological use. 相似文献
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223.
Payne Brennan R.; Jackson Joshua J.; Noh Soo Rim; Stine-Morrow Elizabeth A. L. 《Canadian Metallurgical Quarterly》2011,26(3):738
The current study investigated the nature of the flow state among older adults. Flow is a pleasurable experiential state that occurs during full-capacity engagement in which an individual is performing at a level that is matched with the demands of the task. Each participant completed a scale assessing dimensions of flow in a particular activity selected by the participant. More cognitively demanding activities elicited higher levels of flow for those with higher fluid ability, but lower levels of flow for those with lower fluid ability. This pattern was reversed for activities that were low in demand. Our data highlight the potential importance of considering motivational states such as flow in understanding cognitive optimization in adulthood. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
224.
Single Crystal Formamidinium Lead Iodide (FAPbI3): Insight into the Structural,Optical, and Electrical Properties 下载免费PDF全文
225.
226.
Hong Jae Shin Soo Hong Choi Jae Yi Choi Jae Kyu Park Sung Joong Kim Seong Ho Yun Jeong Rim Seo Sung Joon Bae Han Seop Kim Chang Ho Oh 《Journal of the Society for Information Display》2020,28(6):557-565
In this paper, we present a high image quality organic light‐emitting diode (OLED) display with motion blur reduction technology. Our latest work includes driving method that reduces motion blur using an adaptive black data insertion, brightness compensation technology, the simple structure pixel with low capacitance coupling for horizontal noise, and the multifunction integrated gate driver. The moving picture response time (MPRT) value of the OLED display panel with a fast response time was significantly affected by the frame frequency and the compensation driving method. The MPRT value of the large‐size OLED display panels was significantly decreased by using the integrated gate driver circuit with an MPRT reduction method. The decrease in the MPRT value originated from the turning of the emitting pixels off in advance resulting from providing black data. The integrated gate drivers were designed to achieve the normal display, the black data insertion, and the compensation mode. The MPRT value of the 65‐in. ultrahigh‐definition (UHD) OLED panels was decreased to 3.4 ms by using an integrated gate driver circuit. The motion blur of large‐size OLED display panels was significantly reduced due to a decrease in the MPRT value. 相似文献
227.
Yu‐Rim Hong Kang Min Kim Jeong Ho Ryu Sungwook Mhin Jungin Kim Ghulam Ali Kyung Yoon Chung Sukhyun Kang HyukSu Han 《Advanced functional materials》2020,30(38)
The development of earth‐abundant and efficient oxygen evolution reaction (OER) electrocatalysts is necessary for green hydrogen production. The preparation of efficient OER electrocatalysts requires both the adsorption sites and charge transfer on the catalyst surface to be suitably engineered. Herein, the design of an electrocatalyst is reported with significantly enhanced water oxidation performance via dual‐phase engineering, which displays a high number of adsorption sites and facile charge transfer. More importantly, a simple chemical etching process enables the formation of a highly metallic transition boride phase in conjunction with the transition metal hydroxide phase with abundant adsorption sites available for the intermediates formed in the OER. In addition, computational simulations are carried out to demonstrate the water oxidation mechanism and the real active sites in this engineered material. This research provides a new material design strategy for the preparation of high‐performance OER electrocatalysts. 相似文献
228.
Handling noise in textual image resolution enhancement using online and offline learned dictionaries
Walha Rim Drira Fadoua Lebourgeois Frank Garcia Christophe Alimi Adel M. 《International Journal on Document Analysis and Recognition》2018,21(1-2):137-157
International Journal on Document Analysis and Recognition (IJDAR) - The resolution enhancement of textual images poses a significant challenge mainly in the presence of noise. The inherent... 相似文献
229.
Wan-Tack Rim Kwang-Joon Kim Chong-Won Lee 《Journal of Mechanical Science and Technology》1990,4(1):48-53
Natural frequencies are used to identify the joint stiffness of a shaft-bearing system, where the shaft is assumed as a Rayleigh
beam and the bearing as a linear spring. The eigenvalues for the case of uniform circular shaft are derived in a rigorous
manner in terms of nondimensionalized parameters for the location of bearngs, bearing stiffness, and slenderness of the shaft.
Then, sensitivities of the eigenvalues are calculated with respect to the stiffness ratio of shaft and bearing and the bearing
location. Based upon these sensitivity charts, an iterative procedure is proposed to identify the bearing stiffness in an
optimum sense. The step by step procedure is illustrated through a case study for a simple shaft-bearing system, where the
stiffness of a set of ball bearings is successfully identified. 相似文献
230.
In this paper we address the problem of modeling and analyzing human motion by focusing on 3D body skeletons. Particularly, our intent is to represent skeletal motion in a geometric and efficient way, leading to an accurate action–recognition system. Here an action is represented by a dynamical system whose observability matrix is characterized as an element of a Grassmann manifold. To formulate our learning algorithm, we propose two distinct ideas: (1) in the first one we perform classification using a Truncated Wrapped Gaussian model, one for each class in its own tangent space. (2) In the second one we propose a novel learning algorithm that uses a vector representation formed by concatenating local coordinates in tangent spaces associated with different classes and training a linear SVM. We evaluate our approaches on three public 3D action datasets: MSR-action 3D, UT-kinect and UCF-kinect datasets; these datasets represent different kinds of challenges and together help provide an exhaustive evaluation. The results show that our approaches either match or exceed state-of-the-art performance reaching 91.21% on MSR-action 3D, 97.91% on UCF-kinect, and 88.5% on UT-kinect. Finally, we evaluate the latency, i.e. the ability to recognize an action before its termination, of our approach and demonstrate improvements relative to other published approaches. 相似文献