• Journal of the Korean Magnetic Resonance Society
• /
• v.11 no.2
• /
• pp.85-94
• /
• 2007

Vanilloid receptor I [transient receptor potential vanilloid subfamily member 1 (TRPV1), also known as VR1] is a non-selective cationic channel activated by noxious heat, vanilloids, and acid, thereby causing pain. VR1 possesses six transmembrane domain and N-and C-terminus cytosolic domains, and appears to be a homotetramer. We studied the structural properties of Cterminus of VR1 (VR1C) using CD and NMR spectroscopy. DPC micelles, with a zwitterionic surface, and SDS micelles, with a negatively charged surface, were used as a membrane mimetic model system. Both SDS and DPC micelles could increase the stability of helical structures and/or reduce the aggregation form of the VR1C. However, the structural changing mode of the VR1C induced by the SDS and DPC micelles was different. The changes according to the various pHs were also different in two micelles conditions. Because the net charges of the SDS and DPC micelles are negative and neutral, respectively, we anticipate that this difference might affect the structure of the VR1C by electrostatic interaction between the surface of the VR1C and phospholipids of the detergent micelles. Based on these similarity and dissimilarity of changing aspects of the VR1C, it is supposed that the VR1C probably has the real pI value near the pH 7. Generally, mild extracellular acidic pH ($6.5{\sim}6.8$) potentiates VRI channel activation by noxious heat and vanilloids, whereas acidic conditions directly activate the channel. The channel activation of the VRI might be related to the structural change of VR1C caused by pH (electrostatic interactions), especially near the pH 7. By measuring the $^1-^{15}N$ TROSY spectra of the VR1C, we could get more resolved and dispersed spectra at the low pH and/or detergent micelles conditions. We will try to do further NMR experiments in low pH with micelles conditions in order to get more information about the structure of VR1C.

• Journal of the Korean Magnetics Society
• /
• v.21 no.3
• /
• pp.83-87
• /
• 2011

We have analyzed the torque signals measured in synthetic antiferromagnetic (SAF) coupled CoFeB/Ru/CoFeB thin film, which signals were drastically changed at flopping field ($H_F$) and saturation field ($H_s$). The minimum value of negative uniaxial anisotropy constant ($-\;K_1$) was appeared at HF. The $-\;K_1$ was due to the zero net magnetization by the antiferromagnetic coupling between two ferromagnetic layers. Whereas, the biaxial anisotropy constant (K2) was induced in the field range of $H_F$ < H < $H_s$. The induced $K_2$ was originated from deviation angles between magnetization directions of two ferromagnetic layers. And at H > $H_s$, intrinsic uniaxial anisotropy constant of CoFeB layer was observed. These change of the anisotropy constant with magnetic field was explained by the magnetization process of two ferromagnetic layers based on Stoner-Wohlfarth model calculation for SAF thin film.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.54 no.8
• /
• pp.55-64
• /
• 2017

In this paper, we propose and implement an IoT based mobile smart monitoring system in the view point of safety inspection for solar power generation. The main features and contributions of proposed system are as follows. First, the proposed system model can evaluate periodically in the view point of safety inspection the conditions of the system and structure of solar power generation. Second, the proposed system automatically re-processes the measurement data of the system and structure for solar power generation and save it into database. Third, using the re-processed and saved information, the proposed system can provide the monitoring information with webpage form to both administrator and owner of solar power generation system, thus they can measure and confirm directly in the view point of safety inspection the conditions of the solar generation structure without visiting those places. Fourth, the provided web pages for the monitoring of solar power generation can be accessed regardless of the system structures. The performance evaluations of the proposed system show that the proposed monitoring system can save efficiently the data received from the sensors installed in the structure of solar power generation into the data base in the collecting server. And the proposed system can support that both administrator and user of solar power generation system access webpage in real time without considering places by using mobile phone and desktop computer and obtain the information for the conditions of the system and structure of solar power generation with graph forms.

• Journal of the Korean GEO-environmental Society
• /
• v.10 no.6
• /
• pp.61-68
• /
• 2009

The main objective of this study was to examine the removal of heavy metals from water by inflated vermiculites. The component of vermiculites was analyzed by XRF, and the concentration of metal ion was measured by ICP-AES. Serial batch kinetic tests and batch sorption tests were conducted to determine the removal characteristics for heavy metals in aqueous solutions. As a result, solution pH values of tests with the inflated vermiculites generally increased and then stabilized. Equilibrium pHs were generally established within 5 hrs. In addition, removal rates of inflated vermiculites were tested at the initial concentration of 3 mg/L. As a result, at equilibrium concentration, except for chromium (36.23%), Most of the heavy metals were effectively removed (96.08~98.54%). Finally, sorption data were correlated with both Langmuir and Freundlich isotherms. The Qmax obtained from Langmuir isotherm were determined to Pb $725.4mg\;kg^{-1}$, Cd $568.8mg\;kg^{-1}$, Zn $540.2mg\;kg^{-1}$, Cu $457.2mg\;kg^{-1}$ Cr $0.9mg\;kg^{-1}$ respectively. The results of the study indicate that inflated vermiculites can be properly used as an adsorbent for various heavy metals because of its outstanding removal rate.

• Economic and Environmental Geology
• /
• v.51 no.6
• /
• pp.531-542
• /
• 2018

Batch sorption experiments were performed to remove the uranium (U) in groundwater by using the bamboo charcoal. For 2 kinds of commercialized bamboo charcoals in Korea, the U removal efficiency at various initial U concentrations in water were investigated and the optimal sorption conditions to apply the bamboo charcoal were determined by the batch experiments with replicate at different pH, temperature, and reaction time conditions. From results of adsorption batch experiments, the U removal efficiency of the bamboo charcoal ranged from 70 % to 97 % and the U removal efficiency for the genuine groundwater of which U concentration was 0.14 mg/L was 84 %. The high U removal efficiency of the bamboo charcoal maintained in a relatively wide range of temperatures ($10{\sim}20^{\circ}C$) and pHs (5 ~ 9), supporting that the usage of the bamboo charcoal is available for U contaminated groundwater without additional treatment process in field. Two typical sorption isotherms were plotted by using the experimental results and the bamboo charcoal for U complied with the Langmuir adsorption property. The maximum adsorption concentration ($q_m:mg/g$) of A type and C type bamboo charcoal in the Langmuir isotherm model were 200.0 mg/g and 16.9 mg/g, respectively. When 2 g of bamboo charcoal was added into 100 mL of U contaminated groundwater (0.04 ~ 10.8 mg/L of initial U concentration), the separation factor ($R_L$) and the surface coverage (${\theta}$) maintained lower than 1, suggesting that the U contaminated groundwater can be cleaned up with a small amount of the bamboo charcoal.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.24 no.4
• /
• pp.218-233
• /
• 2022

The long-term (1986~2020) predictability of the number of days of heat and cold damages for each growth stage of soybean is evaluated using the daily maximum and minimum temperature (Tmax and Tmin) data produced by Pusan National University Coupled General Circulation Model (PNU CGCM)-Weather Research and Forecasting (WRF). The Predictability evaluation methods for the number of days of damages are Normalized Standard Deviations (NSD), Root Mean Square Error (RMSE), Hit Rate (HR), and Heidke Skill Score (HSS). First, we verified the simulation performance of the Tmax and Tmin, which are the variables that define the heat and cold damages of soybean. As a result, although there are some differences depending on the month starting with initial conditions from January (01RUN) to May (05RUN), the result after a systematic bias correction by the Variance Scaling method is similar to the observation compared to the bias-uncorrected one. The simulation performance for correction Tmax and Tmin from March to October is overall high in the results (ENS) averaged by applying the Simple Composite Method (SCM) from 01RUN to 05RUN. In addition, the model well simulates the regional patterns and characteristics of the number of days of heat and cold damages by according to the growth stages of soybean, compared with observations. In ENS, HR and HSS for heat damage (cold damage) of soybean have ranged from 0.45~0.75, 0.02~0.10 (0.49~0.76, -0.04~0.11) during each growth stage. In conclusion, 01RUN~05RUN and ENS of PNU CGCM-WRF Chain have the reasonable performance to predict heat and cold damages for each growth stage of soybean in South Korea.

• Neonatal Medicine
• /
• v.17 no.2
• /
• pp.181-192
• /
• 2010

Purpose: Current studies have demonstrated the neuroprotective effects of dizocilpine (MK-801) in many animal models of brain injury, including hypoxic-ischemic (HI) encephlopathy, trauma and excitotoxicity, but limited data are available for those during the neonatal periods. Here we investigated whether dizocilpine can protect the developing rat brain from HI injury via anti-apoptosis. Methods: In an in vitro model, embryonic cortical neuronal cell culture of Sprague-Dawley (SD) rats at 18-day gestation was done. The cultured cells were divided into three groups: normoxia (N), hypoxia (H), and hypoxia treated with dizocilpine (HD). The N group was prepared in 5% $CO_2$ incubators and the other groups were placed in 1% $O_2$ incubators (94% N2, 5% $CO_2$) for 16 hours. In an in vivo model, left carotid artery ligation was done in 7-day-old SD rat pups. The animals were divided into six groups; hypoxia (N), hypoxia (H), hypoxia with sham-operation (HS), hypoxia with operation (HO), HO treated with vehicle (HV), and HO treated with dizocilpine (HD). Hypoxia was made by exposure to a 2 hour period of hypoxic incubator (92% N2, 8% $O_2$). Results: In the in vitvo and in vivo models, the expressions of Bcl-2 in the hypoxia groups were reduced compared to the normoxia group. whereas those in the dizocilpine-treated group were increased compared to the hypoxia group. However. the expressions of Bax and caspase-3 and the ratio of Bax/Bcl-2 were revealed reversely. Conclusion: Dizocilpine has neuroprotective property over perinatal HI brain injury via anti-apoptosis.

• Neonatal Medicine
• /
• v.18 no.1
• /
• pp.59-69
• /
• 2011

Purpose: Current studies have demonstrated the neuroprotective effects of 6-cyano-7-nitroquinoxalin-2,3-dione (CNQX) in many animal models of brain injury, including hypoxic-ischemic (HI) encephlopathy, trauma and excitotoxicity, but limited data are available for those during the neonatal periods. Here we investigated whether CNQX can protect the developing rat brain from HI injury via mediation of nitric oxide synthase. Methods: In an in vivo model, left carotid artery ligation was done in 7-day-old Sprague-Dawley (SD) rat pups. The animals were divided into six groups; normoxia (N), hypoxia (H), hypoxia with sham-operation (HS), hypoxia with operation (HO), HO treated with vehicle (HV), and HO treated with CNQX at a dose of 10 mg/kg (HC). Hypoxia was made by exposure to a 2 hr period in the hypoxic chamber (92% $N_2$, 8% $O_2$). In an in vitro model, embryonic cortical neuronal cell culture of SD rats at 18-day gestation was done. The cultured cells were divided into three groups: normoxia (N), hypoxia (H), and hypoxia treated with CNQX (HC). The N group was prepared in 5% $CO_2$ incubators and the other groups were placed in 1% $O_2$) incubators (94% $N_2$, 5% $CO_2$) for 16 hr. Results: In the in vitvo and in vivo models, the expressions of iNOS and eNOS were reduced in the hypoxia group when compared to the normoxia group, whereas they were increased in the CNQX-treated group compared to the hypoxia group. In contrast, the expression of nNOS was showed reversely. Conclusion: CNQX has neuroprotective property over perinatal HI brain injury via mediation of nitric oxide synthase.

• Journal of Chest Surgery
• /
• v.39 no.12 s.269
• /
• pp.879-890
• /
• 2006

Background: The dysfunction of multiple organs is found to be caused by reactive oxygen species as a major modulator of microvascular injury after hemorrhagic shock. Hemorrhagic shock, one of many causes inducing acute lung injury, is associated with increase in alveolocapillary permeability and characterized by edema, neutrophil infiltration, and hemorrhage in the interstitial and alveolar space. Aggressive and rapid fluid resuscitation potentially might increased the risk of pulmonary dysfunction by the interstitial edema. Therefore, in order to improve the pulmonary dysfunction induced by hemorrhagic shock, the present study was attempted to investigate how to reduce the inflammatory responses and edema in lung. Material and Method: Male Sprague-Dawley rats, weight 300 to 350 gm were anesthetized with ketamine(7 mg/kg) intramuscular Hemorrhagic Shock(HS) was induced by withdrawal of 3 mL/100 g over 10 min. through right jugular vein. Mean arterial pressure was then maintained at $35{\sim}40$ mmHg by further blood withdrawal. At 60 min. after HS, the shed blood and Ringer's solution or 5% albumin was infused to restore mean carotid arterial pressure over 80 mmHg. Rats were divided into three groups according to rectal temperature level($37^{\circ}C$[normothermia] vs $33^{\circ}C$[mild hypothermia]) and resuscitation fluid(lactate Ringer's solution vs 5% albumin solution). Group I consisted of rats with the normothermia and lactate Ringer's solution infusion. Group II consisted of rats with the systemic hypothermia and lactate Ringer's solution infusion. Group III consisted of rats with the systemic hypothermia and 5% albumin solution infusion. Hemodynamic parameters(heart rate, mean carotid arterial pressure), metabolism, and pulmonary tissue damage were observed for 4 hours. Result: In all experimental groups including 6 rats in group I, totally 26 rats were alive in 3rd stage. However, bleeding volume of group I in first stage was $3.2{\pm}0.5$ mL/100 g less than those of group II($3.9{\pm}0.8$ mL/100 g) and group III($4.1{\pm}0.7$ mL/100 g). Fluid volume infused in 2nd stage was $28.6{\pm}6.0$ mL(group I), $20.6{\pm}4.0$ mL(group II) and $14.7{\pm}2.7$ mL(group III), retrospectively in which there was statistically a significance between all groups(p<0.05). Plasma potassium level was markedly elevated in comparison with other groups(II and III), whereas glucose level was obviously reduced in 2nd stage of group I. Level of interleukine-8 in group I was obviously higher than that of group II or III(p<0.05). They were $1.834{\pm}437$ pg/mL(group I), $1,006{\pm}532$ pg/mL(group II), and $764{\pm}302$ pg/mL(group III), retrospectively. In histologic score, the score of group III($1.6{\pm}0.6$) was significantly lower than that of group I($2.8{\pm}1.2$)(p<0.05). Conclusion: In pressure-controlled hemorrhagic shock model, it is suggested that hypothermia might inhibit the direct damage of ischemic tissue through reduction of basic metabolic rate in shock state compared to normothermia. It seems that hypothermia should be benefit to recovery pulmonary function by reducing replaced fluid volume, inhibiting anti-inflammatory agent(IL-8) and leukocyte infiltration in state of ischemia-reperfusion injury. However, if is considered that other changes in pulmonary damage and inflammatory responses might induce by not only kinds of fluid solutions but also hypothermia, and that the detailed evaluation should be study.

• Economic and Environmental Geology
• /
• v.51 no.2
• /
• pp.87-97
• /
• 2018

The cesium (Cs) removal from the contaminated water system has been considered to be difficult because the cesium likes to exist as soluble phases such as ion and complexes than the solid in water system. Many researches have focused on developing the breakthrough adsorbent to increase the cesium removal efficiency in water. In this study, the laboratory scale experiments were performed to investigate the feasibility of the adsorption process using the bamboo charcoal for the Cs contaminated water system. The Cs removal efficiency of the bamboo charcoal were measured and the optimal adsorption conditions were determined by the adsorption batch experiments. Total 5 types of commercialized bamboo charcoals in Korea were used to identify their surface properties from SEM-EDS and XRD analyses and 3 types of bamboo charcoals having large specific surface areas were used for the adsorption batch experiment. The batch experiments to calculate the Cs removal efficiency were performed at conditions of various Cs concentration (0.01 - 10 mg/L), pH (3 - 11), temperature ($5-30^{\circ}C$), and adsorption time (10 - 120 min.). Experimental results were fitted to the Langmuir adsorption isotherm curve and their adsorption constants were determined to understand the adsorption properties of bamboo charcoal for Cs contaminated water system. From results of SEM-EDS analyses, the surfaces of bamboo charcoal particles were composed of typical fiber structures having various pores and dense lamella structures in supporting major adsorption spaces for Cs. From results of adsorption batch experiments, the Cs-133 removal efficiency of C type bamboo charcoal was the highest among those of 3 bamboo charcoal types and it was higher than 75 % (maximum of 82 %) even when the initial Cs concentration in water was lower than 1.0 mg/L, suggesting that the adsorption process using the bamboo charcoal has a great potential to remove Cs from the genuine Cs contaminated water, of which Cs concentration is low (< 1.0 mg/L) in general. The high Cs removal efficiency of bamboo charcoal was maintained in a relatively wide range of temperatures and pHs, supporting that the usage of the bamboo charcoal is feasible for various types of water. Experimental results were similar to the Langmuir adsorption model and the maximum amount of Cs adsorption (qm:mg/g) was 63.4 mg/g, which was higher than those of commercialized adsorbents used in previous studies. The surface coverage (${\theta}$) of bamboo charcoal was also maintained in low when the Cs concentration in water was < 1.0 mg/L, investigating that the Cs contaminated water can be remediated up with a small amount of bamboo charcoal.