• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.275-283
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• 2016

An anti-amnesic effect of water extract from Dendropanax morbifera Lev. leaves (DMW) on memory dysfunction in streptozotocin-induced diabetic rats was investigated to assess its potential industrial value. Daily administration of DMW (11 weeks) significantly reduced serum glucose, insulin, and blood urea nitrogen (BUN) levels increased by an intraperitoneal injection of streptozotocin (STZ, 55 mg/kg). In addition, the administration of DMW decreased escape latency and increased the time spent in the platform quadrant in the Morris water maze test. Step-through latency in a passive avoidance test was also improved. Finally, DMW produced ameliorating effects on STZ-induced cholinergic deficit through an inhibitory effect on acetylcholinesterase and the increment of acetylcholine level in the hippocampus. These results suggest that DMW might be used as a natural substance for improving diabetic induced cognitive impairment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.799-806
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• 2014

The present study was conducted to evaluate the effects of extract from Eriobotrya japonica leaves (EJE) on cognitive impairment induced by scopolamine, a muscarinic antagonist, in rats. Scopolamine injection (1 mg/kg, i.p.) impaired performance in rats in the passive avoidance test as well as in water maze test and severely reduced cholinergic system reactivity, as indicated by reduced acetylcholine levels and increased acetylcholinesterase activity. Daily administration of EJE significantly increased step-through latency in the passive avoidance test, reduced escape latency, and increased time spent in the platform quadrant in the Morris water maze test. EJE protected against scopolamine-induced cholinergic system deficit, including reduced acetylcholine levels and increased acetylcholinesterase activity in whole brain homogenates. These results suggest that EJE provides a significant anti-amnesic effect against scopolamine-induced cholinergic system deficits and cognitive impairment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1190-1196
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• 2013

The purpose of this study was to investigate the mechanism and effects of different types of ginseng on memory improvement in an experimental rat model. In this study, SD rats were induced for memory deficits through scopolamine treatment (1 mg/kg, i.p.) then administrated with ginseng extract for 7 weeks. The rats were divided into five groups: saline (1 mL/kg, NC: negative control), white ginseng (300 mg/kg, WG), red ginseng (300 mg/kg, RG), black ginseng (300 mg/kg, BG), and scopolamine (1 mg/kg, PC: positive control). The step through latency of the BG and RG groups was significantly longer than the PC group in the retention trial of multiple trial passive avoidance test. In the spatial reference memory triads of the Morris water maze test, the latency time of BG and RG was significantly lower than the PC group. In addition, in the prove test, the time spent in the platform quadrant of BG and RG groups were significantly longer than the PC group. Brain choline acetyltransferase (ChAT) activities BG and RG groups significantly increased compared to other groups. On the other hand, the levels of malondialdehyde (MDA) were significantly lower in the BG and RG groups compared to other groups. These result suggested that black ginseng could be useful to enhance learning memory and cognitive function by regulation of cholinergic enzymes.

• Information Systems Review
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• v.18 no.4
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• pp.155-171
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• 2016

Today's organizations make a large investment in information technology (IT) that supports knowledge management. The perceived importance of transactive memory systems (TMS) is increasing in the aspect of team performance. This study aims to understand the mediating effect of knowledge sharing and usage from the perspective of the relationship between IT support for knowledge management and TMS for team performance. To this end, this study analyzes the survey responses obtained from 224 members of 37 different teams using IT support for knowledge management. The results are as follows. First, the effect of IT support on knowledge management was significant in TMS. Second, the mediating effect of IT support on knowledge management through TMS was higher than its direct effect on knowledge sharing and usage. Third, IT support for knowledge management had a greater effect on knowledge sharing than on knowledge usage. Fourth, the effect of TMS appeared to be ordered by tacit knowledge sharing, explicit knowledge sharing, tacit knowledge usage, and explicit knowledge usage. Fifth, the relationship of team performance with knowledge sharing and usage was significant in the order of tacit knowledge usage, tacit knowledge sharing, and explicit knowledge usage.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.269-269
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• 2004

배아줄기 세포는 신경퇴행성 질환의 치료 수단으로 많은 가능성을 가지고 있는 것으로 알려져 있다. 본 연구에서는 중풍 동물모델에서 수중미로 학습을 이용하여 중풍 치료제로서 인간배아줄기 세포의 인지 및 기억력 장애에 대한 기능 회복의 효능을 검토하였고, 인간배아줄기 세포의 신경세포 보호효과를 규명하기 위하여 면역조직화학 염색법을 이용하여 해마내의 세포사멸을 측정하였으며, 인지 및 기억증진의 작용을 규명하기 위하여 아세틸콜린성 신경세포의 활성도를 측정하였다. (중략)

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.209-209
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• 2010

단위면적 당 메모리 집적도를 높이기 위해 플래시 기억소자의 크기를 줄일 때, 절연층 두께 감소에 의한 누설 전류의 발생, 단채널 효과 및 협폭 효과와 같은 문제 때문에 소자 크기의 축소가 한계에 도달하고 있다. 이러한 문제점들을 개선하기 위해 본 연구에서는 FinFET구조위에 Oxide-Nitride-Oxide (ONO) 층을 적층하여 2-비트 특성을 갖는 플래시 메모리 소자를 제안하였다. 소자의 작동전압을 크게 줄일 수 있으며 소자의 크기가 작아질 때 일어나는 단채널 효과의 문제점을 해결할 수 있는 FinFET 구조를 가진 기억소자에서 제어게이트를 제어게이트1과 제어게이트2로 나누어 독립적으로 쓰기 및 소거 동작하도록 하였다. 2-비트 동작을 위해 제어 게이트1의 게이트 절연막의 두께를 제어게이트2의 게이트 절연막의 두께보다 더 얇게 함으로써 두 제어게이트 사이의 coupling ratio를 다르게 하였다. 제어게이트1의 트랩층의 두께를 제어게이트2의 트랩층의 두께보다 크게 하여 제어게이트1의 트랩층에 더 많은 양의 전하가 포획될 수 있도록 하였다. 제안한 기억소자가 2-비트 동작하는 것을 확인 하기위하여 2차원 시뮬레이션툴인 MEDICI를 사용하여 제시한 FinFET 구조를 가진 기억소자의 전기적 특성을 시뮬레이션하였다. 시뮬레이션을 통해 얻은 2-비트에 대한 각 상태에서 각 전하 포획 층에 포획된 전하량의 비교를 통해서 coupling ratio 차이와 전하 포획층의 두께 차이로 인해 포획되는 전하량이 달라졌다. 각 상태에서 제어게이트에 읽기 전압을 인가하여 전류-전압 특성 곡선을 얻었으며, 각 상태에서의 문턱전압들이 잘 구분됨을 확인함으로써 제안한 FinFET 구조를 가진 플래시 메모리 소자가 셀 당 2-비트 동작됨을 알 수 있었다.

• Korean Journal of Communication Studies
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• v.18 no.1
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• pp.165-193
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• 2010

The current study has significance in that it increases our understanding of BPL effectiveness by adding long-term memory dependent variables to widely used short-term memory variables. Furthermore, two unit of analysis of the current study, subject and BPL, made richer analysis possible as compared to previous studies. The result showed that BPL was effective in short-term recognition(52.8% of BPLs), long-term recognition(44.4% of BPLs), and long-term recall(30.6% of BPLs). The further result showed that audiovisual BPL, closeup BPL, long-exposed brand, leading actor using brand were more effective than other kinds of BPL. On the other hand, preference for the movie and preference for the actor were not significant factors in increasing people's memory of the brand name. Future researchers should settle the confusion existed in this field by inventing a more elaborate research design and exploring mediating and moderating variables in the subject of BPL effectiveness.

• Korean Journal of Cognitive Science
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• v.19 no.3
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• pp.311-330
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• 2008

The effect of spatial attention gradually decreases as a function of the distance between the locus of attention and a target. According to this hypothesis, we tested the spatial-effect profile of visual attention when it operates on perception and memory. Experiment 1 measured accuracy of discriminating the color of a simultaneously masked target after presenting a pre-cue to either at the target location or away from the target (perception-intensive task). Experiment 2 measured accuracy of recognizing the color of several items at and around the pre-cued location (memory-intensive task). In the perception-intensive condition, the accuracy gradually dropped as the distance between the cue and target location increases. However, in the memory-intensive condition, subjects remembered only the item at the cued location. This suggests spatial attention in a memory-intensive process would operate on object-based representations. Experiment 2 showed the object-based effect observed in Experiment 1 can be also present in perception under a special circumstance. The results indicate that spatial attention can operate on object-based representations in a memory-intensive process whereas it flexibly can operate either on location-based or object-based representations in a perception-intensive process.

• The Journal of the Convergence on Culture Technology
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• v.4 no.3
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• pp.261-267
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• 2018

In the present study, we assessed the effecs of fruit and vegetable bark resources rich in beneficial substances on the learning ability and memory improvement. It functions to inhibit the activity of acetylcholinesterase in brain tissue and improve cognitive functions in a simulation model of cognitive impairment induced by scopolamine. Hence, it can promote memory and learning ability. The formulation of the fruit and vegetable bark uses the extract of fruit and vegetable peels, which has long been used without causing toxicity in a wide range of food applications. Therefore, it can be used safely without a risk of side effects, even in the case of a long-term administration for the preventive purpose. Furthermore, the present study is a very beneficial study in the environment-friendly aspect in association with recycling of resources as it is based on the novel efficacies of fruit and vegetable barks which have been conventionally disposed as a refuse of fruits due to their poor sensory qualities despite the content of beneficial substances.

• Journal of Ginseng Research
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• v.24 no.1
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• pp.8-17
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• 2000

Estrogen can influence on the expression of behaviors not associated directly with reproduction, including learning and memory. Recently estrogen has received considerable attention for its effects on neuroprotection and neural circuits in brain areas associated with cognition. Although estrogen replacement therapy may be helpful to postmenopausal women, it also results in a number of harmful side effects. Ginseng also has steroidal qualities and contains several ginsenoside components which have similar backbone structure to estrogen. The objectives of this experiment were 1) to examine the effects of estrogen and 2) to investigate the effects of ginsenosides as estrogenic agent on learning and memory using the Morris water maze, a traditional experimental task for spatial memory. In the experiments designed here, ovariectomized mice were implanted subcutaneously with Sila, itic capsules containing 17${\beta}$-estradiol (100∼250 $\mu\textrm{g}$/$m\ell$), panaxadiol (PD) and panaxatriol (PT) saponins (15∼100 $\mu\textrm{g}$/$m\ell$) diluted with sesame oil. In the first set of experiment, the effects of estradiol on learning and memory during the Morris water maze was examined. When estradiol was delivered via Silastic capsules following training improved spatial memory performance in ovariectomized female mice. In the second set of experiment, three different PD and PT saponin concentrations were delivered via Silastic implants to ovariectomized female mice and their effects were compared with estrogenic effects. Results of three separate experiments demonstrated that estradiol, PD and PT administrated by Silastic implants for 2 weeks prior to water maze training significantly improved spatial memory performance compared to ovariectomized (OVX) mice, as indicated by lower escape latency over trial. The positive effect of estradiol suggests that estrogen can affect performance on learning and memory. In addition, the positive effect of PD and PT saponins suggest that ginsenosides have an estrogen-like effects in mediating learning and memory related behavior action.