• Journal of Korean Biological Nursing Science
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• 제21권3호
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• pp.217-223
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• 2019

Purpose: Caffeine is the most widely consumed psychostimulant of the methylxanthine class. Among adolescents, high-dose of caffeine consumption has increased rapidly over the last few decades due to the introduction of energy drinks. However, little is known about the time-dependent effect of high doses of caffeine consumption in adolescents. The present study aims to examine the short- and long-term influence of high-dose caffeine on behavior of adolescence. Methods: The animals were divided into three groups: a "vehicle" group, which was injected with 1 ml of phosphate-buffered saline for 14 days; a "Day 1" group, which was injected with caffeine (30 mg/kg), 2 h before the behavioral tests; and a "Day 14" group, which was infused with caffeine for 14 days. An open-field test, a Y-maze test, and a passive avoidance test were conducted to assess the rats'activity levels, anxiety, and cognitive function. Results: High-dose caffeine had similar effects in short-and long-term treatment groups. It increased the level of locomotor activity and anxiety-like behavior, as evidenced by the increase in the number of movements and incidences of rearing and grooming in the caffeine-treated groups. No significant differences were observed between the groups in the Y-maze test. However, in the passive avoidance test, the escape latency in the caffeine-treated group was decreased significantly, indicating impaired memory acquisition. Conclusion: These results indicate that high-dose caffeine in adolescents may increase locomotor activity and anxiety-like behavior and impair learning and memory, irrespective of the duration of administration. The findings will be valuable for both evidence-based education and clinical practice.

• Clinical and Experimental Pediatrics
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• 제57권3호
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• pp.101-109
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• 2014

The use of glucocorticoids (GCs) in the perinatal period is suspected of being associated with adverse effects on long-term neurodevelopmental outcomes for preterm infants. Repeated administration of antenatal GCs to mothers at risk of preterm birth may adversely affect fetal growth and head circumference. Fetal exposure to excess GCs during critical periods of brain development may profoundly modify the limbic system (primarily the hippocampus), resulting in long-term effects on cognition, behavior, memory, co-ordination of the autonomic nervous system, and regulation of the endocrine system later in adult life. Postnatal GC treatment for chronic lung disease in premature infants, particularly involving the use of dexamethasone, has been shown to induce neurodevelopmental impairment and increases the risk of cerebral palsy. In contrast to studies involving postnatal dexamethasone, long-term follow-up studies for hydrocortisone therapy have not revealed adverse effects on neurodevelopmental outcomes. In experimental studies on animals, GCs has been shown to impair neurogenesis, and induce neuronal apoptosis in the immature brains of newborn animals. A recent study has demonstrated that dexamethasone-induced hypomyelination may result from the apoptotic degeneration of oligodendrocyte progenitors in the immature brain. Thus, based on clinical and experimental studies, there is enough evidence to advice caution regarding the use of GCs in the perinatal period; and moreover, the potential long-term effects of GCs on brain development need to be determined.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권1호
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• pp.39-45
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• 2007

Extracts of adult worker bodies of Vespa simillima in 2 % NaCl or acidified methanol were administered orally to mice for 70 days. Following this period, memory at one-day and one-month periods, and the effects on scopolamine-induced amnesia were examined using a step-through passive avoidance task. Changes in MK-801-induced disability after 8 days of training, and in memory one month after the trial were also assessed. Mice treated with the 2% NaCl extract showed significant improvement in memory in the behavioral tests one month after the trial, whereas mice receiving the extract in acidified methanol, did not differ from the controls in any trial. The results inidicate that Vespa simillima contains substances acting favorably on the cerebral functions of mammals.

• 한국콘텐츠학회논문지
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• 제22권2호
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• pp.224-236
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• 2022

본 연구는 도시슬로건의 사용이 경우에 따라서는 도시 관련 기억의 인출에 부정적 영향을 미칠 수 있음을 전제로 관련 변수의 효과를 실험적으로 고찰하고 있다. 가설 검정을 위해 본 연구는 4 실험집단(2(슬로건의 도시 관련성: 고 혹은 저) × 2(슬로건의 구체성: 고 혹은 저)과 1개의 통제집단을 구성하였다. 실험집단은 각 조건에 맞은 도시슬로건에 도출되었으며, 통제집단은 도시슬로건에 노출되지 않았다. 이후 각 집단의 기억인출 점수를 비교하게 된다. 표본은 대학 학부생 174명으로 구성되었으며, 남자 54%, 연령 분포 만 18-27세, 연령 평균 만 22.4세이다. 연구결과 도시슬로건은 슬로건과 관련 없는 도시기억의 인출을 방해하는 경우가 많은 것으로 나타났다. 이러한 방해효과는 슬로건이 도시와 관련성이 높을수록, 구체적일수록 더 커지는 것으로 나타났다. 그러나 도시 관련성이 낮고 구체성이 낮은 슬로건에서는 방해효과가 발견되지 않았다. 본 연구는 기존 연구와 달리 도시슬로건의 부정적 효과를 다루고 있다는 차별성을 가질 뿐만 아니라 실무적으로도 관련 담당자들에게 도시슬로건의 제정과 관련된 전략적 시사점을 제공하고 있다.

• Advances in Traditional Medicine
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• 제7권2호
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• pp.182-190
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• 2007

Alzheimer's disease is a neurodegenerative disorder associated with a decline in cognitive abilities. Dementia is one of the aged related mental problems and a characteristic symptom of Alzheimer's disease. Nootropic agents like piracetam and cholinesterase inhibitors like $Donepezil^{\circledR}$ are used in situations where there is organic disorder in learning abilities, but the resulting side-effects associated with these agents have limited their utility. Foeniculum (F.) vulgare Linn. is widely used in Indian traditional systems of medicines and also as a house remedy for nervous debility. The present work was undertaken to assess the potential of F. vulgare as a nootropic and anti-cholinesterase agent in mice. Exteroceptive behavioral models such as Elevated plus maze and Passive avoidance paradigm were employed to assess short term and long term memory in mice. To delineate the possible mechanism through which F. vulgare elicits the anti-amnesic effects, its influence on central cholinergic activity was studied by estimating the whole brain acetylcholinesterase activity. Pretreatment of methanolic extract of fruits of F. vulgare Linn. for 8 successive days, ameliorated the amnesic effect of scopolamine (0.4 mg/kg) and aging induced memory deficits in mice. F. vulgare extract significantly decreased transfer latencies of young mice and aged mice, increased step down latency and exhibited significant anti-acetyl cholinesterase effects, when compared to piracetam, scopolamine and control groups of mice. F. vulgare might prove to be a useful memory restorative agent in the treatment of dementia seen in the elderly.

• Molecules and Cells
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• 제27권1호
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• pp.5-14
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• 2009

The availability of effective vaccines has had the most profound positive effect on improving the quality of public health by preventing infectious diseases. Despite many successful vaccines, there are still old and new emerging pathogens against which there is no vaccine available. A better understanding of how vaccines work for providing protection will help to improve current vaccines as well as to develop effective vaccines against pathogens for which we do not have a proper means to control. Recent studies have focused on innate immunity as the first line of host defense and its role in inducing adaptive immunity; such studies have been an intense area of research, which will reveal the immunological mechanisms how vaccines work for protection. Toll-like receptors (TLRs), a family of receptors for pathogen-associated molecular patterns on cells of the innate immune system, play a critical role in detecting and responding to microbial infections. Importantly, the innate immune system modulates the quantity and quality of long-term T and B cell memory and protective immune responses to pathogens. Limited studies suggest that vaccines which mimic natural infection and/or the structure of pathogens seem to be effective in inducing long-term protective immunity. A better understanding of the similarities and differences of the molecular and cellular events in host responses to vaccination and pathogen infection would enable the rationale for design of novel preventive measures against many challenging pathogens.

• Journal of Information Processing Systems
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• 제17권5호
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• pp.867-878
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• 2021

In context awareness and user intention tasks, dataset construction is expensive because specific domain data are required. Although pretraining with a large corpus can effectively resolve the issue of lack of data, it ignores domain knowledge. Herein, we concentrate on data domain knowledge while addressing data scarcity and accordingly propose a multi-channel long short-term memory (LSTM). Because multi-channel LSTM integrates pretrained vectors such as task and general knowledge, it effectively prevents catastrophic forgetting between vectors of task and general knowledge to represent the context as a set of features. To evaluate the proposed model with reference to the baseline model, which is a single-channel LSTM, we performed two tasks: voice phishing with context awareness and movie review sentiment classification. The results verified that multi-channel LSTM outperforms single-channel LSTM in both tasks. We further experimented on different multi-channel LSTMs depending on the domain and data size of general knowledge in the model and confirmed that the effect of multi-channel LSTM integrating the two types of knowledge from downstream task data and raw data to overcome the lack of data.

• 한국기계가공학회지
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• 제20권12호
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• pp.85-91
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• 2021

In our daily life, artificial intelligence performs simple and complicated tasks like us, including operating mobile phones and working at homes and workplaces. Artificial intelligence is used in industrial technology for diagnosing various types of equipment using the machine learning technology. This study presents a fault mode effect analysis (FMEA) of start motors using machine learning and big data. Through multiple data collection, we observed that the primary failure of the start motor was caused by the melting of the magnetic switch inside the start motor causing it to fail. Long-short-term memory (LSTM) was used to diagnose the condition of the magnetic locations, and synthetic data were generated using the synthetic minority oversampling technique (SMOTE). This technique has the advantage of increasing the data accuracy. LSTM can also predict a start motor failure.

• Smart Structures and Systems
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• 제29권4호
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• pp.599-616
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• 2022

Bridge displacement contains vital information for bridge condition and performance. Due to the limits of direct displacement measurement methods, the indirect displacement reconstruction methods based on the strain or acceleration data are also developed in engineering applications. There are still some deficiencies of the displacement reconstruction methods based on strain or acceleration in practice. This paper proposed a novel method based on long short-term memory (LSTM) networks to reconstruct the bridge dynamic displacements with the strain and acceleration data source. The LSTM networks with three hidden layers are utilized to map the relationships between the measured responses and the bridge displacement. To achieve the data fusion, the input strain and acceleration data need to be preprocessed by normalization and then the corresponding dynamic displacement responses can be reconstructed by the LSTM networks. In the numerical simulation, the errors of the displacement reconstruction are below 9% for different load cases, and the proposed method is robust when the input strain and acceleration data contains additive noise. The hyper-parameter effect is analyzed and the displacement reconstruction accuracies of different machine learning methods are compared. For experimental verification, the errors are below 6% for the simply supported beam and continuous beam cases. Both the numerical and experimental results indicate that the proposed data fusion method can accurately reconstruct the displacement.

• 한국경영과학회지
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• 제22권3호
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• pp.37-58
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• 1997

An AI approach with tabu search is designed to solve multi-level knapsack problems. The approach performs intelligent actions with memories of historic data and learning effect. These action are developed ont only by observing the attributes of the optimal solution, the solution space, and its corresponding path to the optimal, but also by applying human intelligence, experience, and intuition with respect to the search strategies. The approach intensifies, or diversifies the search process appropriately in time and space. In order to create a good neighborhood structure, this approach uses two powerful choice rules that emphasize the impact of candidate variables on the current solution with respect to their profit contribution. "Pseudo moves", similar to "aspirations", support these choice rules during the evaluation process. For the purpose of visiting as many relevant points as possible, strategic oscillation between feasible and infeasible solutions around the boundary is applied. To avoid redundant moves, short-term (tabu-lists), intemediate-term (cycle-detection), and long-term (recording frequency and significant solutions for diversfication) memories are used. Test results show that among the 45 generated problems (these problems pose significant or insurmountable challenges to exact methods) the approach produces the optimal solutions in 39 cases.lutions in 39 cases.