• Title/Summary/Keyword: Activity Coefficient

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Perchlorate Ion-Selective PVC Membrane Electrode Based on the Quaternary Ammonium Salts (제4급 암모늄염을 이용한 과염소산 이온선택성 PVC막 전극)

  • 안형환;김용렬;강현춘;이한섭;이병철;강안수
    • Membrane Journal
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    • v.3 no.3
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    • pp.126-135
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    • 1993
  • Perchlorate ion-selective PVC membrane electrode responsive to $10^{-6}M$ was developed by incorporating the ion-pair complex of perchlorate with the quaternary ammonium salts as a active material. The effect of chemical structure, the content of active material, the kinds of plasticizers, and the membrane thickness on the electrode characteristics such as the linear response range and Nernstian slope of the electrode were studied. With the results, the useful pH range and the selectivity coefficients to various interfering anions were compared and investigated. It was obtained that the effect of the chemical structure of an active material on the electrode characteristics was improved with increasing the alkyl chain length of the quarternary ammonium salts in the ascending order of Aliquat 336P, TOAP, TDAP, and TDDAP. The electrode characteristics was improved with the decrease of the active material content below the optimum membrane composition, and DBP was the best as a plasticizer. The optimum membrane composition was 9.09wt% of TDDAP, 30.3wt% of PVC, and 60.6wt% of ptasticizer(DBP). And the optimum membrane thickness was0.45mm at this composition. Under the above condition, thelinear response ranger was $10^{-1}~1.2 {\times} 10^{-6}M$, and the detection limit was $5.1{\times}10^{-7}M$ with the Nernstian slope of 57mV/decade of activity of perchlorate ion. The electrode potential was stable within the pH range from 4 to 11. The selectivity coefficient was as shown below : $SCN^->I^->NO_3^->Br^->ClO_3^->F^->Cl^->SO_4^{2-}$

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N-Methyl-D-Aspartate (NMDA) Receptor Antagonistic Effect and Ginsenoside Content of Panax ginseng C. A. Meyer Cultivar Root Extracts (인삼 품종별 뿌리 추출물의 NMDA 수용체 길항 효과 및 진세노사이드 함량)

  • Lee, Seung Eun;Kim, Jang Uk;Jeong, Hyeon Soo;Choi, Je Hun;Ji, Yun Jeong;Kim, Hyung Don;Jang, Gwi Yeong;Hyun, Dong Yun;Kim, Dong Hwi
    • Korean Journal of Medicinal Crop Science
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    • v.28 no.1
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    • pp.9-20
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    • 2020
  • Background: Although a number of Panax ginseng cultivars have been developed by Korean researchers in recent years, there has been insufficient analysis of their beneficial properties. In this study, we sought to identify useful ginseng varieties as functional materials. Methods and Results: We evaluated effects of root extracts of 10 ginseng cultivars (Cheongsun; CS, Chunpoong; CP, Gopoong; GP, Gumpoong; GMP, K1, Sunhyang; SH, Sunone; SO, Sunpoong; SP, Sunun; SU and Yunpoong; YP) against the inhibitory effects of nitric oxide (NO) and reactive oxygen species (ROS) production in mouse brain microglial BV2 cells, as well as the binding of N-methyl-D-aspartate receptor (NMDAR), a marker related to memory. Ginsenosides, such as 20 (S)-protopanaxadiols (PPDs), including ginsenoside-Rb1, -Rb2, -Rb3, -Rc, -Rd, and - Rg3 and 20 (S)-protopanaxatriols (PPTs) including -Re, -Rg1, and -Rg2 were analyzed by HPLC. We observed that the cultivar GMP showed the highest inhibitory effect (60.8%) against NO production at 20 ㎍/㎖. Those cultivars showing the significantly highest inhibition effects against ROS at 20 ㎍/㎖ were K1 (57.3%), SP (54.5%), YP (53.1%), CP (51.7%), CS (50.9%) and SH (49.6%). At 50 ㎍/㎖, K1 showed the most potent inhibitory effect (51.2%) on NMDAR binding. The total phenol content of SH (1.89 mg/g) and K1 (1.73 mg/g) were higher than those of the other cultivars, whereas in terms of PD/PT ratios, the values of CP (0.98), K1 (1.05) and SO (1.05) were lower than those of the other cultivars. On the basis of correlation coefficient (0.7064) between NMDAR inhibition and ONOO- scavenging activity. Conclusions: The findings of this study indicate that the cultivars K1 and SH could be useful ginseng resources as functional materials with favorable cognition-improving and antioxidative properties.

The effects of Maternal Parenting Behavior, Smart Devices Addiction, and Children's Self Regulation on Their Use of Smart Devices (유아의 자기조절, 어머니의 양육행동과 스마트기기 중독이 유아의 스마트기기 이용에 미치는 영향)

  • Kim, Min Hee
    • Korean Journal of Childcare and Education
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    • v.11 no.6
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    • pp.133-151
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    • 2015
  • The aim of this study was to examine how children's self control, mother's addiction to smart devices and parenting behavior influence the way young children used smart devices. Participants were made up of 166 preschoolers and their mothers. Descriptive analysis, Pearson's correlation coefficient, and hierarchical regression analysis were used for statistical analysis. The results were as follows: First, children in their early childhood years used smart devices once or twice a week, for ten to thirty minutes, mainly during weekends. Children in their early childhood stage started to use smart devices before reaching the age of 3, and accessed them through their parents, usually along with their siblings. Parents allowed their children to use smart devices for fun and entertainment, with only 66.3% of them setting rules. Second, the mother's tendency to be immersed in smart devices, overprotection and permission were positively correlated to young children's overusage of smart devices, whereas geniality, encouragement, setting limits, and children's self control were negatively correlated. The study also found that the mother's tendency of being immersed in smart devices was the most influential factor for their children's overusage of smart devices. The value of this study lies in providing practical suggestions for children's smart device usage and parental education programs.

The Level of Awareness and Practice in Prehospital Emergency Patient Assessment and Emergency Care of Paramedic in Fire Station (1급 응급구조사의 병원 전 응급환자평가와 응급처치시행에 대한 인식과 실천정도)

  • Kang, Yong-Ju;Choi, En-Sook
    • The Korean Journal of Emergency Medical Services
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    • v.15 no.2
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    • pp.67-84
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    • 2011
  • Purpose: The aim of this study is to present the basic data for qualitative improvement of emergency care for emergency patient by paramedic in fire station by understanding the level of awareness and practice in prehospital and transfer step, and understanding the level of emergency care and improvement of clinical knowledge through hospital clinical training. Methods: The researchers explained the objective for 143 persons who completed hospital clinical training from June 2nd, 2006 to October 23rd, 2009 among paramedic in fire station. The questionnaire in this research consisted of 80 questions. In the reliability for the awareness of emergency patient assessment, cronbach's $\alpha$ was 0.95, and in the reliability for emergency care fulfillment, cronbach's $\alpha$ was 0.93. reliability for clinical knowledge improvement is cronbach's $\alpha=.95$, and reliability for emergency care fulfillment is cronbach's $\alpha=.82$. Collected data was analyzed through SPSS 18.0 statistics program for frequency, percentage, average, standard deviation, Paired t-test, t-test, Correlation Coefficient, and internal consistency reliability was analyzed by cronbach's $\alpha$. Results: 1) The paramedic awareness and practice difference for emergency patient is statistically signification for general patient assessment(t=14.159, p=.000), trauma patient assessment(t=11.288, p=.000), internal medicine patient assessment(t=10.898, p=.000), and it shows the level of practice is lower than the level of awareness. 2) The paramedic difference between the level of awareness and practice according to whether or not they have clinical career is not signification on awareness(t=3.119, p=.125), and is high on practice(t=3.119, p=.002). 3) The correlation between paramedic awareness and the level of practice shows positive correlation(r=.61, p=.000). The higher the awareness of emergency patient assessment is, the higher the level of practice is. 4) The difference between paramedic clinical knowledge improvement and the level of emergency care practice is statistically significant(t=3.351, p=.001). 5) 89.6%(128 persons) of paramedic replied hospital clinical training experiences are helpful for field activity. 92.3%(133 persons) replied they apply well for clinical knowledge learned during hospital clinical training and emergency care skills in the field. Conclusion: Paramedic in fire station must evaluate the patient's initial assessment and activate the transfer system to the emergency department. It is necessary to develop and implement the effective education program continuously. The education program should systemize currently operated hospital clinical training. emergency disease and symptoms emergency care method, and practice mainly skill education should be progressed. In the prehospital and transfer management, high quality of medical assessment is required to the emergency medical service system. Medical direction from the doctors can feedback the paramedic continuously and continuing education must be provided to the paramedic in fire station.

Effect of Preadmission Metformin Use on Clinical Outcome of Acute Respiratory Distress Syndrome among Critically Ill Patients with Diabetes

  • Jo, Yong Suk;Choi, Sun Mi;Lee, Jinwoo;Park, Young Sik;Lee, Chang-Hoon;Yim, Jae-Joon;Yoo, Chul-Gyu;Kim, Young Whan;Han, Sung Koo;Lee, Sang-Min
    • Tuberculosis and Respiratory Diseases
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    • v.80 no.3
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    • pp.296-303
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    • 2017
  • Background: Acute respiratory distress syndrome (ARDS) is related to high mortality and morbidity. There are no proven therapeutic measures however, to improve the clinical course of ARDS, except using low tidal volume ventilation. Metformin is known to have pleiotropic effects including anti-inflammatory activity. We hypothesized that pre-admission metformin might alter the progress of ARDS among intensive care unit (ICU) patients with diabetes mellitus (DM). Methods: We performed a retrospective cohort study from January 1, 2005, to April 30, 2005 of patients who were admitted to the medical ICU at Seoul National University Hospital because of ARDS, and reviewed ARDS patients with DM. Metformin use was defined as prescribed within 3-month pre-admission. Results: Of 558 patients diagnosed with ARDS, 128 (23.3%) patients had diabetes and 33 patients were treated with metformin monotherapy or in combination with other antidiabetic medications. Demographic characteristics, cause of ARDS, and comorbid conditions (except chronic kidney disease) were not different between metformin users and nonusers. Several severity indexes of ARDS were similar in both groups. The 30-day mortality was 42.42% in metformin users and 55.32% in metformin nonusers. On multivariable regression analysis, use of metformin was not significantly related to a reduced 30-day mortality (adjusted ${\beta}-coefficient$, -0.19; 95% confidence interval, -1.76 to 1.39; p=0.816). Propensity score-matched analyses showed similar results. Conclusion: Pre-admission metformin use was not associated with reduced 30-day mortality among ARDS patients with DM in our medical ICU.

A Normalization Method to Utilize Brain Waves as Brain Computer Interface Game Control (뇌파를 BCI 게임 제어에 활용하기 위한 정규화 방법)

  • Sung, Yun-Sick;Cho, Kyung-Eun;Um, Ky-Hyun
    • Journal of Korea Game Society
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    • v.10 no.6
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    • pp.115-124
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    • 2010
  • In the beginning brain waves were used for monkeys to control robot arm with neural activity. In recent years there are research that measured brain waves are used for the control of programs which monitor the progression of dementia or enhance of attention in children diagnosed with Attention Deficit Hyperactivity Disorder (ADHD). Moreover, low-price devices that can be used as a game control interface have become available. One of the problems associated with control using brain waves is that the mean amplitude, mean wavelength, and mean vibrational frequency of the brain waves differ from individual to individual. This paper attempts to propose a method to normalize measured brain waves using normal distribution and calculate the waveforms that can be used in controlling games. For this, a framework in which brain waves are converted in seven stages has been suggested. In addition, the estimation process in each stage has been described. In an experiment the waveforms of two subjects have been compared using the proposed method in the BCI English word learning program. The level of similarity between two subjects' waveforms has been compared with correlation coefficient. When the proposed method was applied, both meditation and concentration increased by 13% and 8%, respectively. Because the proposed regularization method is converted into a waveform fit for control functions by reducing personal characteristics reflected in the brain waves, it is fitting for application programs such as games.

Physicochemical Properties and Antioxidant Activities of Steam-Dried Allium hookeri Root (증포 처리한 삼채 뿌리의 이화학적 특성 및 항산화 활성)

  • Jun, Hyun-Il;Jang, Ha-Na;Yang, Jae-Heon;Song, Geun-Seoup;Kim, Young-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.3
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    • pp.412-417
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    • 2015
  • This study was carried out to investigate the effect of steam-drying method on physicochemical properties and antioxidant activities of Alliun hookeri root (AHR). Moisture, crude protein, crude fat, and crude ash contents of raw and steam-dried AHRs were 10.91~14.15%, 11.14~13.49%, 0.83~3.02%, and 7.55~8.98%, respectively. Sulfur contents of steam-dried AHRs were 2.0 and 2.2 times lower than that of raw AHR (0.51%), respectively. pH and total sugar contents of AHRs were reduced by steam-drying, whereas titrate acidity and browning intensity were increased. The L and b values of AHRs in Hunter's value were also reduced, but a value was increased by steam-drying. Among hot water extracts from raw and steam-dried AHRs, four times steam-drying showed the lowest $EC_{50}$ values (0.44, 9.01, and 0.48 mg/mL, respectively) in DPPH radical assay, ABTS radical assay, and reducing power, whereas four times steam-drying had the highest total phenolic content ($34.47{\mu}g/mg$) and browning intensity (2.05 and 0.20 at 280 and 420 nm, respectively). The antioxidant activities of hot water extracts from raw and steam-dried AHRs were closely correlated with their total phenolic contents and browning intensity, showing coefficient of determination ($R^2$) values higher than 0.87. From the results, we suggest that steam-drying method could be used as an effective process for increasing the antioxidant activity of AHR.

Determinants of Health-Promoting Behavior in the Elderly (노인의 건강증진행위와 관련된 변인에 관한 연구)

  • Kim Hyo-Jung;Park Young-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.4 no.2
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    • pp.283-300
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    • 1997
  • This study was undertaken to grasp health-promoting behavior of the elderly and to identify variables related to them in order to facilitate nursing intervention for health promotion of this population. The subjects for this study were 291 old persons obtained by cluster sampling from twenty general social welfare centers located in Tague. Data were collected by self-reported questionnaires from August 13 to September 13, 1996. Questionnaires were developed based on Sherer and others' Self-Efficacy scale, Rosenberg's Self-Esteem scale, Wallston and other's Multidimensional Health Locus of Control scale, Northern illinois University's Helath Self Rating Scale, Walker and others' Health Promotion Lifestyles Profile. Analysis of the data was done by use of descriptive statistics, stepwise multiple regression, Pearson Correlation Coefficient, MANOVA, t-test, and ANOVA. The results were summarized as follows : 1. For the practice of health-promoting behavior, the mean score was 2.89 and range was 3.59 to 2.09. The factor of the highest mean score was regular diet(M=3.42) and factor of the lowest mean score as stress management(M=2.27). 2. The combination of self-efficacy, internal health locus of control, family number, and average monthly pocket money explained 30.0% of the variance of health-promoting behavior. 3. With regard to the relationship between health-promoting behavior and cognitive perceptual factor, self-efficacy correlated positively with health-promoting behavior(r=.4951, P=.0001), self-esteem correlated positively(r=.3263, P=.0001), internal health locus of control correlated positively(r=.3244, P=.0001), perceived health status correlated positively(r=.1355, P=.0274). 4. According to age(F=2.50, P=.0431), sex(t=2.14, P=.0332), marital status(F=7.85, P=.0005), education(F=5.44, P=.0003), family number(F=11.18, P=.0001), people living together(F=7.21, P=.0009), previous occupation(F=5.83, P=.0001), average monthly pocket money(F=7.27, P=.0001), there were differences of health-promoting behavior. The above findings show that health-promoting behavior are related to demographic characteristics, four cognitive perceptual factors(self-efficacy, self-esteem, internal health locus of control, perceived health status). On the basis of the above findings the following recommendations are made ; 1. Nursing interventions enhancing exercise or activity, accountability for health, stress management of the elderly must be provided. 2. Nursing strategies enhancing self-efficacy which is most significant effect on health-promoting behavior must be developed.

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The Correlation of Brain Natriuretic Peptide (BNP), Pulmonary Arterial Pressure, and St. George Respiratory Questionnaire (SGRQ) and Their Changes with a Trial of an Angiotensin Converting Enzyme Inhibitor (폐동맥고혈압이 동반된 만성폐쇄성폐질환 환자에서 혈중 Brain Natriuretic Peptide, 폐동맥압 및 St. George Respiratory Questionnaire의 상관성과 안지오텐신전환효소억제제 치료 효과)

  • Kim, Myung-A;Kim, Deog-Kyeom;Lee, Chang-Hoon;Chung, Hee-Soon
    • Tuberculosis and Respiratory Diseases
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    • v.68 no.5
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    • pp.273-279
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    • 2010
  • Background: Pulmonary hypertension is considered as a poor prognosis factor in patients with chronic obstructive pulmonary disease (COPD). There has been reported brain natriuretic peptide (pro-BNP) is related with increased right ventricular (RV) workloads. However, there are few studies that evaluate the relationship between BNP and pulmonary arterial pressure (PAP), RV function and St. George Respiratory Questionnaire (SGRQ) score in patients with COPD, and the effects of angiotensin converting enzyme inhibitor (ACEI) on these parameters. Methods: Pulmonary function test, echocardiography, blood BNP, and SGRQ score were evaluated in stabilized moderate degree COPD patients ($FEV_1$/FVC< 70%, $50%{\leq}FEV_1$ < 80%) aged 45 years and over, without worsening of symptoms within recent 3 months. After treating with ramipril 10 mg for 3 months, the same evaluation was repeated. Results: Twenty-two patients were included in this study. BNP was significantly correlated with PAP (Pearson coefficient ${\rho}=0.51$, p=0.02), but not with RV ejection fraction (EF) and predicted $FEV_1%$. The values for predicted $FEV_1%$ showed significant correlation with SGRQ total score and activity score, but not with BNP or PAP. After ramipril treatment, PAP showed significant decrease ($42.8{\pm}8.1$ vs. $34.5{\pm}4.5mm$ Hg p=0.0003), tricuspid annular plane systolic excursion significant increase ($21.5{\pm}3.3$ vs. $22.7{\pm}3.1mm$ p=0.009). BNP showed a tendency to decrease without statistical significance ($40.8{\pm}59.6$ vs. $18.0{\pm}9.1pg/mL$ p=0.55). SGRQ scores showed no significant change. Conclusion: BNP showed significant correlation with resting PAP, which means BNP could be used as markers for pulmonary hypertension. Treatment with ACEI didn't show significant change in the level of BNP, while pulmonary hypertension and RV function were improved.

Relative Importance of Bottom-up vs. Top-down Controls on Size-structured Phytoplankton Dynamics in a Freshwater Ecosystem: II. Investigation of Controlling Factors using Statistical Modeling Analysis (담수성 식물플랑크톤의 크기별 동태에 대한 상향식, 하향식 조절간의 상대적 중요도 조사: II. 통계 모델링 분석을 이용한 조절인자 분석)

  • Song, Eun-Sook;Lim, Jang-Seob;Chang, Nam-Ik;Sin, Yong-Sik
    • Korean Journal of Ecology and Environment
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    • v.38 no.4 s.114
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    • pp.445-453
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    • 2005
  • Relative importance between bottom-up and top-down controls on phytoplankton dynamics was investigated in the Juam Reservoir, Chonnam based on the results from statistical analyses including regression and artificial neural network (ANN) modeling. Effects of nutrients on size-structured phytoplankton dynamics were explored by simple linear regression analysis and relative importance between bottom-up and top-down controls was estimated based on results from the artificial neural network analyses. Although there is a limitation in determining direct grazing effects since chlorophyll a : pheopigments ratios, indirect index for grazing activity rather than grazing rates or herbivores biomass were used, the results from regression analysis showed that nutrients especially orthophosphates were positively correlated with the phytoplankton biomass and chlorophyll a : pheopigments ratios were also positively correlated with the phytoplankton biomass at lower coefficient of determination ($r^2$) compared to orthophosphates. The simulation results from ANN suggested that the bottom-up mechanisms including water temperature and availability of nutrients, especially orthophosphates were more important than top-down mechanisms such as grazing in the phytoplankton dynamics.