• Korean Journal of Materials Research
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• v.26 no.11
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• pp.604-610
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• 2016

We report on the fabrication and characterization of a novel $Cu_2O/CuO$ heterojunction structure with CuO nanorods embedded in $Cu_2O$ thin film as an efficient photocathode for photoelectrochemical (PEC) solar water splitting. A CuO nanorod array was first prepared on an indium-tin-oxide-coated glass substrate via a seed-mediated hydrothermal synthesis method; then, a $Cu_2O$ thin film was electrodeposited onto the CuO nanorod array to form an oxide semiconductor heterostructure. The crystalline phases and morphologies of the heterojunction materials were examined using X-ray diffraction and scanning electron microscopy, as well as Raman scattering. The PEC properties of the fabricated $Cu_2O/CuO$ heterojunction photocathode were evaluated by photocurrent conversion efficiency measurements under white light illumination. From the observed PEC current density versus voltage (J-V) behavior, the $Cu_2O/CuO$ photocathode was found to exhibit negligible dark current and high photocurrent density, e.g. $-1.05mA/cm^2$ at -0.6 V vs. $Hg/HgCl_2$ in $1mM\;Na_2SO_4$ electrolyte, revealing the effective operation of the oxide heterostructure. The photocurrent conversion efficiency of the $Cu_2O/CuO$ photocathode was estimated to be 1.27% at -0.6 V vs. $Hg/HgCl_2$. Moreover, the PEC current density versus time (J-T) profile measured at -0.5 V vs. $Hg/HgCl_2$ on the $Cu_2O/CuO$ photocathode indicated a 3-fold increase in the photocurrent density compared to that of a simple $Cu_2O$ thin film photocathode. The improved PEC performance was attributed to a certain synergistic effect of the bilayer heterostructure on the light absorption and electron-hole recombination processes.

• Journal of Chest Surgery
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• v.35 no.4
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• pp.267-273
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• 2002

Background: We performed a phase IV clinical trial to examine the usefulness of a continuous infusion of nicardipine hydrochloride to control hypertension in patients with acute aortic dissection. material and Method: Systolic/diastolic blood pressure, and heart rate were monitored before and after the intravenous administration of nicardipine in 31 patients with aortic diseases. The period of nicardipine administration in each patient was from 3 to 14 days. Efficacy was evaluated by determining the average amount of blood pressure reduction on the 3rd day of drug administration. The dosage of another antihypertensive agent was slowly tapered down, and ultimately replaced by the test drug. Result: 28 patients were diagnosed as acute aortic dissection, 2 patients as rupture of the aortic arch aneurysm, and 1 patient as traumatic aortic rupture. Mean age was 53.9 $\pm$ 14.9(29~89) years, and 21 patients(67.7%) were male. 14 patients(32.3%) had complications associated with underlying aortic disease: aortic insufficiency in 7, hemopericardium in 6, acute renal failure in 1, paraplegia in 1, lower extremity ischemia in 1, and hemothorax in 1. The time needed to reach the target blood pressure was within 15 minutes in 16, from 15 to 30 minutes in 10, from 30 to 45 minutes in 3 and from 45 to 60 minutes in 2, and their baseline average systolic, diastolic, and mean arterial blood pressures(mmHg) were 147$\pm$23, 82.3$\pm$ 18.6, and 104 $\pm$ 18, respectively. Average systolic, diastolic, and mean arterial blood pressures(mmHg) on the third day of nicardipine infusion were 119$\pm$ 12, 69$\pm$9, and 86$\pm$8, and they all showed statistically significant decrease(p<0.05). The average systolic, diastolic, and mean arterial blood pressure(mmHg) after the discontinuation of the nicardipine infusion were 119 $\pm$ 15, 71 $\pm$ 14, and 86$\pm$ 13, respectively. No significant difference was observed between the average pressures measured on the third day and those measured after the discontinuation of the nicardipine infusion, and no definite side effects were observed during the study period. Conclusion: Nicardipine hydrochloride was both effective and safe at controlling blood pressure in patients with acute aortic dissection.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.6-14
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• 2008

Objective of this study was to investigate the residual levels of mercury (Hg) in soil for "Top-rice" area and its uptake into rice plant for making sure food safety as compared to "Top-rice" & common rice produced from 2005 to 2006. Hg was analyzed with the direct mercury analyzer (DMA 80, Milestone, Italy), which implements the US/EPA method 7473. The average concentration of Hg in paddy soil was 0.031 mg/kg, which was below at 1/25-1/65 fold of the threshold levels (concern level 4 mg/kg, action level 10 mg/kg) for soil contamination designated by "The Soil Environment Conservation Law" in Korea. The maximum residue level (MRLs) for Hg residue in the polished rice is not designated in Korea. Therefore, Hg contents in the polished rice of "Top-rice" brand and common rice were compared to other country's criteria. Hg contents in the polished rice of "Top-rice" brand was 0.0018 mg/kg, which was lower at 1/10-1/30 fold than the MRLs, 0.02 mg/kg of China criteria and 0.05 mg/kg of Taiwan criteria, respectively. Hg were 0.02788, 0.00896, 0.00182, 0.00189, 0.00166, 0.00452 and 0.00145 mg/kg in soil, rice straw, unhulled rice, rice hulls, brown rice, rice bran, and polished rice produced in 2006 "Top-rice" area, respectively. For the ratio of Hg as compared to Hg contents in soil, there were 0.321 of rice straw ${\gg}$ 0.162 of rice bran ${\gg}$ 0.068 of rice hulls > 0.065 of unhulled rice > 0.060 of brown rice> 0.052 of polished rice. And, the slope of Hg uptakes was steeped as following order; rice straw ${\gg}$ rice bran ${\gg}$ rice hulls > unhulled rice > brown rice > polished rice. It means that the more slope steeped was the more uptakes. For the distribution of Hg uptaken, there was 83.8% into rice straw, and 16.2% into unhulled rice, 2.8% into rice hulls, 12.4% into brown rice, 3.5% into rice bran and 9.7% into polished rice. Consequently, it was appeared that the Hg contamination in the polished rice should not be worried in Korea.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.218-221
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• 1999

Magnetization measurements have been carried out on grain aligned Hg-1223 with the applied field parallel to the c-axis. The temperature dependence of the lower critical field H$_{cl}$(T) was determined by considering the effect of the surface barrier on the magnetization. H$_{cl}$(T) have been determined .from magnetic hysteresis loops within the framework of the modified Kim-Anderson critical-state model, where the surface barrier and the lower critical field are explicitly considered. At high temperature, H$_{cl}$(T) is identified as H$_p$(T). This results are agreed with the theory of Bean-Livinston surface barriers.

• The Korean Journal of Physiology
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• v.16 no.2
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• pp.147-152
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• 1982

The present study was undertaken to investigate effects of Perillae Folium juice on the respiration and blood pressure in cats. Also studied was the mechanism of depressor action of PFJ. The results obtained are as follows; 1) Following administration of 0.2 ml/kg, 0.4 ml/kg and 0.6 ml/kg PFJ into cats the maximum depressor responses observed were 48.5+3.6 mmHg, 56.8+4.3 mmHg and 71.1+2.9 mmHg respectively. 2) Depressor responses to PFJ were blocked makedly by atropine and partially by propranolol. Therefore it is strongly suggested that depressor action of PFJ results mainly from cholinergic effect and partly from activity of ${\beta}-receptor$. 3) After administration of PFJ into cats tachypnea preceded by a short period of apnea was observed invariably.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.908-915
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• 1994

It was attempted to observe the antidotic effects of garlic on mercury intoxicated rat model in vivo. The experimental model group consists of garlic juice treated group (G), garlic juice-mercury treated group(MG), mercury treated group (M), and control group (basal diet), The garlic juice of 2% to the daily diet by weight was administered orally to G and MG groups, The single dose of 2.5mgHG/Kg per week was given orally to M and MG groups. the study was carried out for 4 weeks. The results of experiment were as follows. For the group of Mg, and the weight increasing rate was improved to about 30% compared to that of group M. Furthermore a general tonic efficay of garlic was observed in G group in term of increased weight gain rate (bout 15%) than control. In the biochemical studies of rat blood garlic showed effects on lowering the abnormally elevated GPT, GOT, uric acid creatinine value, and especially in lowering the BUN value of Hg treated rat that was selectively elevated in the case of impared renal function such as acute gromerulonephritis caused by Hg intoxication. In the analytical studies blood and renal Hg contents. HG group showed lower value (0.3, 0.33ppm) than that of M group (0.46, 0.51 ppm) Significant difference in reducing Hg level due to the antidotic effect of garlic was observed. In conclusion, it was revealed out from this research, the main principles of garlic, nonprotein sulfur amino acid (alliin) and sulfur compounds (allicin and diallyl disulfides) seem to almost certainly have an antidotic effect on mercury intoxication of rat in vivo.

• Journal of Korean Physical Therapy Science
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• v.10 no.2
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• pp.96-103
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• 2003

The purpose of this study was to assess the effect of applied pressure to abdomen on lumbar and abdominal muscle activation during upper limb exercise. The experimental group consisted of twenty-seven healthy male subjects (mean age=$22.40{\pm}2.19years$, mean height=$175.30{\pm}2.19cm$, mean weight= $67.67{\pm}7.44kg$, RM=$8.43{\pm}2.76kg$). In each different pressure condition (OmmHg, 30mmHg, 70mmHg, 100mmHg), upper limb exercise was performed in total of 10 trials with 10 RM dumb-bell exercise. Lumbar and abdominal muscle activity was measured using surface bipolar electrode electromyography(EMG). EMG activity was measured from upper rectus abdominis, external oblique abdominis, internal oblique abdominis, and elector spinae. The raw EMG signal was processed into the root mean square(RMS). All RMS EMG data were normalized and express as a percentage of the EMG(%EMG). Collected data were statistically analyzed by SPSS/PC Ver 10.0 using two-way analysis of variance for repeated measures($4{\pm}3$) and Bonferroni post hoc, test. Lumbar and abdominal muscle activation was significantly increased when 100 mmHg was applied(p<.05). Upper rectus abdominis activation was significantly increased compared as other muscles activation(p<.05). However, there were no interaction between pressure and muscles(p>.05). The findings of this study can be used as a fundamental data when lumbar orthosis is applied and external pressure can be used as a therapeutic tool.

• Korean Circulation Journal
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• v.54 no.2
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• pp.93-104
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• 2024

Backgrounds and Objectives: This study aimed to evaluate the applicability and precision of a ring-type cuffless blood pressure (BP) measurement device, CART-I Plus, compared to conventional 24-hour ambulatory BP monitoring (ABPM). Methods: Forty patients were recruited, and 33 participants were included in the final analysis. Each participant wore both CART-I Plus and ABPM devices on the same arm for approximately 24 hours. BP estimation from CART-I Plus, derived from photoplethysmography (PPG) signals, were compared with the corresponding ABPM measurements. Results: The CART-I Plus recorded systolic blood pressure (SBP)/diastolic blood pressure (DBP) values of 131.4±14.1/81.1±12.0, 132.7±13.9/81.9±11.9, and 128.7±14.6/79.3±12.2 mmHg for 24-hour, daytime, and nighttime periods respectively, compared to ABPM values of 129.7±11.7/84.4±11.2, 131.9±11.6/86.3±11.1, and 124.5±13.6/80.0±12.2 mmHg. Mean differences in SBP/DBP between the two devices were 1.74±6.69/-3.24±6.51 mmHg, 0.75±7.44/-4.41±7.42 mmHg, and 4.15±6.15/-0.67±5.23 mmHg for 24-hour, daytime, and nighttime periods respectively. Strong correlations were also observed between the devices, with r=0.725 and r=0.750 for transitions in SBP and DBP from daytime to nighttime, respectively (both p<0.001). Conclusions: The CART-I Plus device, with its unique ring-type design, shows promising accuracy in BP estimation and offers a potential avenue for continuous BP monitoring in clinical practice.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.495-499
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• 2000

The relative affinity of seaweed alginate, polyguluronate and polymannuronate for cations was investigated. The cations used in this study were $Ca^{2+}$, $Cd^{2+}$, $Co^{2+}$, $Cu^{2+}$, $Fe^{3+}$, $Hg^{2+}$, $Mg^{2+}$, $Mn^{2+}$, $Pb^{2+}$, $Rb^{1+}$, $Sr^{2+}$ and $Zn^{2+}$. The ability of cations to precipitated polymers was determined as the relative affinity of seaweed alginate, polyguluronate and polymannuronate for cations. The relative affinity of polymers for cations in order are as follow: Seaweed alginate: $Fe^{3+}$,$Cu^{2+}$,$Cd^{2+}>Pb^{2+}>Co^{2+}$,$Zn^{2+}>Ca^{2+}>Sr^{2+}$,$Rb^{1+}>Mn^{2+}>Mg^{2+}$,$Hg^{2+}$ Ployguluronate:$Fe^{3+}$,$Cu^{2+}$,$Cd^{2+}>Ca^{2+}$,$Co^{2+}$,$Pb^{2+}>Sr^{2+}$,$Rb^{1+}$,$Zn^{2+}>Hg^{2+}$,$Mn^{2+}>Mg^{2+}$ Polymannuronate:$Fe^{3+}$,$Cd^{2+}$,$Cu^{2+}>Ca^{2+}$,$Pb^{2+}>Zn^{2+}$,$Rb^{1+}$$Sr^{2+}$,$Hg^{2+}>Co^{2+}>Mn^{2+}>Mg^{2+}$

• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.581-595
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• 1994

To investigate the effect of carbon disulfide on blood pressure, the BP measurements in the periodic health examination results and the medical records of factory clinic were reviewed. The study subjects were composed of 1336 male and 544 female workers, who were categorized into three groups by the exposure status-highly exposed, moderately exposed and non-exposed group. The results of the study were as follows; 1. The age-adjusted mean systolic and diastolic BP of male workers were 122.35 mmHg/79.11 mmHg in highly exposed, 121.57mmHg/79.05mmHg in moderately exposed and 122.67mmHg/82.27mmHg in non-exposed group. For female workers, BPs were 115.13mmHg/74.49mmHg in moderately exposed and 113.48mmHg/74.30mmHg in non-exposed group. 2. In multiple regression analysis of maximum BP against Age and tenure, the slope coefficients of age and tenure on the systolic BP were 0.379, 0.667 respectively and those on the diastolic BP were 0.331, 0.405 respectively in highly exposed male workers. Tenure was a significant variable in this study. For female workers, however the slope coefficients of tenure on BP were significant only for systolic BP of moderately-exposed group. 3. In multiple regression analysis of Bp against age, cumulative exposure index (CEI), cholesterol, all the variables showed significant slope coefficients in male, but age and CEI on systolic BP were significant for female workers (p<0.05). 4. In the multiple analysis of the amount of Bp change and the velocity of Bp change among male workers, the slope coefficients of tenure tended to increase as exposure level increased. Among female workers, the slope coefficients of tenure were significant on the amount of Bp change and the velocity of Bp change in moderately exposed group.