• Fisheries and Aquatic Sciences
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• v.25 no.11
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• pp.572-578
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• 2022

An organism's physiological processes and behaviors are regulated by neuropeptides and hormone peptides. The first neuropeptide identified from echinoderms is SALMFamide. The two most well-studied SALMFamide neuropeptides are S1 and S2, which possess myoactivity on apical muscle, tube feet, and the cardiac stomach of starfishes. However, neuropeptide candidates identified from SALMFamide's precursor protein sequence have not been investigated. This study aims to compare the bioactivity of SALMFamide neuropeptides from the starfish Asterias rubens using various starfish muscle preparations. In this study, the bioactivity of the L-type SALMFamide neuropeptides from the starfish A. rubens, AYHTGLPFamide (SALMFa-A) and the derivative AYHSALMFamide (SALMFa-B) was investigated. The neuropeptides were applied on Asterias amurensis apical muscle, tube feet, which revealed that the neuropeptides exhibit relaxing activity on apical muscle but no activity on tube feet. The native SALMFa-A peptide had lower relaxing activity on the apical muscle compared to the derivative peptide SALMFa-B. The relaxing activity of two neuropeptides also was compared with those on the apical muscle of Patiria pectinifera, which revealed relaxing activity as well as SALMFamide-S1 and S2 neuropeptides. Moreover, the investigation of SALMFa-A and SALMFa-B peptides' bioactivity on P. pectinifera cardiac stomach muscle also showed slight relaxing activity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.3
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• pp.148-152
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• 2005

A novel neuropeptide with a relaxing activity on the dorsal retractor muscle (DRM) was isolated from the whole body extract of the starfish, Asterina pectinifera. The peptide was purified by gel-filtration ion-exchange and $C_{18}$ reversed-phase HPLC. The complete amino acid sequence of this peptide, which was determined by automated Edman degradation and MALDI-TOF mass, was Phe-Gly-Lys-Gly-Gly-Ala-Tyr-Asp-Pro-Leu-Ser-Ala-Gly-Phe-Thr-Asp. A comparison of the amino acid sequence with those of other known neuropeptides revealed that the asteripectin was a novel neuropeptide with smooth muscle-relaxing activity on the starfish DRM. This peptide showed threshold response to relaxing activity on the DRM at $10^{-10}M$ and the maximal relaxing effect was $120{\pn}7.0\%$ at $10^{-5}M$. The relaxing activity of this peptide on the starfish DRM increased in a dose-dependent manner.

• Journal of Communications and Networks
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• v.15 no.3
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• pp.283-291
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• 2013

In this paper, we propose new multiuser detectors (MUDs) based on compressed sensing approaches for the large-scale multiple antenna systems equipped with dozens of low-power antennas. We consider the scenarios where the number of receiver antennas is smaller than the total number of users, but the number of active users is relatively small. This prior information motivates sparsity-embracing MUDs such as sparsity-embracing linear/nonlinear MUDs where the detection of active users and their symbol detection are employed. In addition, sparsity-embracing MUDs with maximum a posteriori probability criterion (MAP-MUDs) are presented. They jointly detect active users and their symbols by exploiting the probability of user activity, and it can be solved efficiently by introducing convex relaxing senses. Furthermore, it is shown that sparsity-embracing MUDs exploiting common users' activity across multiple symbols, i.e., frame-by-frame, can be considered to improve performance. Also, in multiple multiple-input and multiple-output networks with aggressive frequency reuse, we propose the interference cancellation strategy for the proposed sparsity-embracing MUDs. That first cancels out the interference induced by adjacent networks and then recovers the desired users' information by exploiting the low user activity. In simulation studies for binary phase shift keying modulation, numerical evidences establish the effectiveness of our proposed MUDs exploiting low user activity, as compared with the conventional MUD.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.1
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• pp.69-74
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• 2016

The present study was undertaken to investigate the influence of cardamonin on vascular smooth muscle contractility and to determine the mechanism(s) involved. Denuded aortic rings from male rats were used and isometric contractions were recorded and combined with molecular experiments. Cardamonin significantly relaxed fluoride-, phenylephrine-, and phorbol ester-induced vascular contractions, suggesting that it has an anti-hypertensive effect on agonist-induced vascular contraction regardless of endothelial nitric oxide synthesis. Furthermore, cardamonin significantly inhibited the fluoride-induced increase in pMYPT1 level and phenylephrine-induced increase in pERK1/2 level, suggesting inhibition of Rho-kinase and MEK activity and subsequent phosphorylation of MYPT1 and ERK1/2. This study provides evidence that the relaxing effect of cardamonin on agonist-induced vascular contraction regardless of endothelial function involves inhibition of Rho-kinase and MEK activity.

• The Korean Journal of Zoology
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• v.10 no.2
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• pp.1-8
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• 1967

토끼의 골격근 homogenate에서 23,000$\times$G, 60 분간의 원심분리와 얻은 근 microsome의 ATPase 활성, 근수축에 대한 이완작용, 및 Ca 의 흡수작용을 여러 가지 조건에서 측정하였다. ATPase 활성은 Ca++ Mg++ 양 이온의 존재에 의하여 활성화되며 , 5 mM Mg++ 의 존재하에서는 Ca++ 의 최적농도는 0.1mM이다. Oxalate의 존재하에서는 1 mM 의 Ca++ 이 최적농도이므로 oxalate의 작용은 불용성 Ca-oxalate의 작용은 불용성 Ca-oxalate를 microsome vesicle so 및 medium 내에 침전시켜 유리 Ca++ 농도를 저하시키는 것이라고 생각된다. Microsome의 이완작용은 조제후 120 시간까지 시간에 따라 감소되어 가나, 그이 ATPase 활성은 거의 변화가 없는 것으로 보아 Ca++ + Mg++ -의존성 ATPase 는 이완작용에는 직접 관련이 없는 것으로 해석된다. Oxalatedmlwhswo는 microsome의 Ca++ 흡수량을 현저히 증대시키며 동시에 흡수포화에 도달하는 시간을 지연시킨다. Oxalate의 이러한 효과도 Ca-oxalate의 형성에 기인하는 것으로 해석된다. Microsome 내에 축적되는 Ca 의 량은 ATP 농도가 커질수록 많아진다. 그러나 축적된 Ca 의 량과 ATP 농도사이에 화학정량론적 관계는 없는 것같다.

• Journal of Environmental Science International
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• v.24 no.5
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• pp.689-697
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• 2015

Based on the survey of 4 universities in Tai' an by questionnaire survey and interviews, this study acquired and analyzed the college student users' activity type, utilization frequency, retention time, companion, preference for landscape design style, the importance of the courtyard space's environment and landscape, as well as correlations between primary attributes and activity characteristics of student users. The weight of the university teaching area's courtyard space evaluation index was obtained by Analytical Hierarchy Process. The results indicated that nearly 60% college students select to study and to rest alone as the main activity type, 80% students' utilization frequency is at least two times or more a week. In addition, the relative weight of plant landscape is the highest in the 2nd class indexes of space garden landscape, and its value is 0.113; the relative weight of cleanliness is the highest in the 3rd class indexes of space environment quality, and its value is 0.143. Therefore, it should be attached much importance to constructing the environment and landscape for studying and relaxing, and the factors of cleanliness and plant landscape etc in the further design of courtyard space are taken into full consideration.

• Journal of Biomedical Engineering Research
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• v.26 no.4
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• pp.223-230
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• 2005

This paper presents a new approach to investigate spatial correlation between independent components of brain alpha activity in functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). To avoid potential problems of simultaneous fMRI and EEG acquisitions in imaging pure alpha activity, data from each modality were acquired separately under a 'three conditions' setup where one of the conditions involved closing eyes and relaxing, thus making it conducive to generation of alpha activity. The other two conditions -- eyes open in a lighted room or engaged in a mental arithmetic task, were designed to attenuate alpha activity. Using a Mixture Density Independent Component Analysis (MD-ICA) that incorporates flexible non-linearity functions into the conventional ICA framework, we could identify the spatiotemporal components of fMRI activations and EEG activities associated with the alpha rhythm. Then, the sources of the individual EEG alpha activity component were localized by a Maximum Entropy (ME) method that is specially designed to find the most probable dipole distribution minimizing the localization error in sense of LMSE. The resulting active dipoles were spatially transformed to 3D MRls of the subject and compared to fMRI alpha activity maps. A good spatial correlation was found in the spatial distribution of alpha sources derived independently from fMRI and EEG, suggesting the proposed method can localize the cortical areas responsible for generating alpha activity successfully in either fMRI or EEG. Finally a functional connectivity analysis was applied to show that alpha activity sources of both modalities were also functionally connected to each other, implying that they are involved in performing a common function: 'the generation of alpha rhythms'.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.1
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• pp.52-58
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• 2017

This study was aimed to examine relaxing effects of Acanthopanacis cortex(AC) through nitric oxide(NO) production and phosphodiesterase type 5(PDE-5) inhibition in corpus cavernosum. In order to define the relaxation effects of AC extract, rabbit corpus cavernous tissues were prepared in $2{\times}2{\times}8mm$ sized strip. AC extract ($0.01-3.0mg/m{\ell}$) were treated in contracted strips induced by phenylephrine(PE) and $N{\omega}$-nitro-L-arginine (L-NNA) was treated before AC extract-treated. And calcium chloride($Ca^{2+}$) 1 mM was infused into precontracted strips after pretreatment of AC extract in $Ca^{2+}-free$ krebs-ringer solution. When AC extract was applied to human umbilical vein endothelial cell(HUVEC), cell viability was measured by MTT assay, and NO concentration was measured by Griess reagent system. Ratio of smooth muscles to collagen fibers and eNOS, PDE-5 positive reaction were measured by histochemical and immunohistochemical process on mice corpus cavernosum. AC extract significantly affected relaxion of the cavernous strips, and the pretreatment of L-NNA inhibited AC extract-induced relaxation. Contraction induced by the addition of $Ca^{2+}$ was inhibited by treatment with the AC extract in $Ca^{2+}-free$ solution. In AC group, NO concentration, ratio of smooth muscle to collagen fibers, and eNOS positive reaction were increased, PDE-5 positive reaction was decreased compared to PE group. As a result of the above experiment, it was thought that AC extract inhibits the inflow of extracellular $Ca^{2+}$ by activating cGMP through the increase of eNOS / NO and the decrease of PDE-5 which inhibits cGMP activity, in the corpus cavernosum.

• Journal of the Korean Society of Food Culture
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• v.25 no.6
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• pp.746-754
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• 2010

Rural tourism is primarily a domestic tourism activity with visitors traveling to non-urban areas. The development of local and regionally denominate food is a way to distinguish agricultural production and to promote rural tourism. Therefore, this study addressed how utilizing regional agricultural products results in increasing the intention of tourists to revisit an area. The purposes of this study were 1) to identify the image and motives for visiting Yesan, 2) to determine the importance of purchasing intention and the regional menu produced from local agricultural/special products, and 3) to identify the impact of purchasing local agricultural/special products and regional menus on the intention to revisit. A total of 202 usable questionnaires were collected at Ducksan Hotsprings and Suduck Temple in Yean area, which are known tourist attractions. The major findings obtained were as follows: First, Yesan was considered a relaxing place ($3.46{\pm}1.09$), which was the highest ranked image score for a tourist attraction. Second, the highest ranked motive for visiting Yesan was to rest ($3.77{\pm}1.18$). According to these findings, Yesan is a relaxing place, as it is a rural area with no known defined attractions. Third, most tourists (78.7%) recognized the apple as a local agricultural/special product. The intentions to purchase local agricultural/special products and the need for regional dishes in the local restaurant was higher than average. Tourists showed interests ($3.88{\pm}1.16$) in eating regional dishes made with local agricultural/special products at the restaurants. Fourth, a significant impact of purchasing local agricultural/special products and the regional menu was observed on the intention to revisit (p<0.000). The results indicate that it is very important to develop proper regional menus that concur with images of the location and the regional farming products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.3
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• pp.143-147
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• 2005

Relationship between structure and biological activity was performed using the five substance P-related peptides (SPRPs) [mammalian-SP (M-SP), cod-SP (C-SP), trout-SP (T-SP), lungfish-SP (L-SP) and Ranakinin] and four SP analogs [[$His^5$]-SP (5H-SP), [$Gly^5$]-SP (5G-SP), ($Ile^8$)-SP (8I-SP) and ($Trp^8$)-Ranakinin (8W-Ranakinin)]. The circular dichroism (CD) spectra showed that all of the peptides took an unordered structure in buffer solution and artificial liposomes. However, 8W-Ranakinin undergoes conformational changes by being transferred into neutral and acidic liposomes from an unordered structure to more ordered structure. The arterial relaxing effect of the peptides was also studied with guinea-pig aorta (GPA), As a result of the studies, L-SP was about 14-fold more potant than M-SP. The order of potency compared to $EC_{50}$ value was $L-SP{\gg}M-SP>5G-SP{\ge}8I-SP>5H-SP>T-SP$, C-SP, Ranakinin, 8W-Ranakinin.