• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.171-178
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• 1998

The microstructure and properties of plasma-sprayed coatings depend on a great number of spraying parameters, random factors, which lead to vibration in these spraying parameters, may in some degree influence the microstructure and properties of the coatings. Therefore, the property values appear certain distributions, and the description and comparison of the properties of plasma-sprayed coatings should be performed employing statistical analysis. In this paper, $Cr_3C_2$-Nicr coatings of different thickness were sprayed onto stainless steel using atmosphere plasma system and adopting three kinds of gun translation speeds. Then the microhardness measurements were performed on polished surface of the coatings. Forty readings were taken and statistically analyzed by calculating the characteristic values, estimating and comparing the means, and assessing whether they belonged to the Normal or Weibull Distribution. This study has found that statistical analysis could discriminate influence of spraying parameters and coating design on microhardness of the $Cr_3C_2$-Nicr coatings from random vibration, which showed that the microharness of the $Cr_3C_2$-Nicr coatings were related to gun translation speed coating thickness.

• Korean Journal of Acupuncture
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• v.20 no.2
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• pp.93-100
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• 2003

Effects of Wisoo and Baekwhe acupuncture on serum glucose and lipid composition were investigated in high fat diet induced diabetic rat. Plasma glucose, free fatty acids and $\Beta-lipoprotein$ concentration showed a high reduction in wisoo acupuncture group compared to those of control group, however the values of baekwhe acupuncture group showed no significantly different those of control group. Plasma triglyceride and LDL-cholesterol concentration showed a tendency to decrease in the wisoo acupuncture groups, however the values of baekwhe showed no significantly different those of control group. Total cholesterol concentration showed a high reduction in wisoo acupuncture groups and HDL-cholesterol concentration showed a high values in wisoo acupuncture group, however these values no significantly different in all treatment groups.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.20-26
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• 2004

The purpose of this study was to investigate dietary taurine intakes, plasma taurine levels and urinary taurine excretions of women in Seoul(Kangbuk-ku) and Kyunggi(Yeoju) area, Korea. Seventy married women aged 39.7$\pm$8.9 have volunteered for this study: 36 from Seoul area and 34 from Kyunggi area. Diet samples were collected from the participants and the samples included three meals (breakfast, lunch and supper), snacks, drinks and whatever the participants had eaten for 24 hours. The plasma was obtained by allowing a 5 $m\ell$ fasting blood sample to be in a heparinized tube for 30 min and centrifuging it at 11,000${\times}$g for 20 min. The collected diets were blended, centrifuged and deproteinized. Taurine levels in the diet and plasma were determined as the dabsyl derivative using HPLC with Rf-detector. The intake of taurine ranged from 6.8 to 837.8 mg/day and its mean value was l45.5$\pm$164.0 mg/day (mean$\pm$SD). The 90th, 50th and 10th percentile values of the taurine intake were 280.0, 94.3 and 26.8 mg/day, respectively. There was a significant difference between two groups: 202.0$\pm$204.9 for Seoul area and 85.5$\pm$67.2 mg/day for Kyunggi area(p<0.00l). The taurine level in plasma ranged from 42.1 to 201.9 $\mu$mol/L and its mean value was 74.9$\pm$22.8 $\mu$mol/L. The 90th, 50th and 10th percentile values of the plasma taurine were 101.1, 70.7 and 54.6 $\mu$mol/L, respectively. There was no significant difference between Seoul area and Kyunggi area in plasma taurine level.

• Nutritional Sciences
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• v.6 no.4
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• pp.232-238
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• 2003

Cardiovascular disease (CVD) is one of the most common causes of death in elderly Koreans, and HDL-cholesterol is known to have a pivotal role in protecting against CVD. This study was undertaken to study the relationships between plasma HDL-cholesterol levels and dietary, anthropometric, and biochemical factors in elderly Koreans. The 102 subjects, who were over 60 years old, were classified into two groups based on their plasma HDL-cholesterol levels: a risk group with plasma HDL-cholesterol < 40mg/dl in men or HDL-cholesterol < 50mg/d1 in women, and a control group with higher HDL-cholesterol levels. The subjects' mean intakes of energy, calcium, zinc, vitamin A, vitamin $B_2$, vitamin E, and folate did not meet the Korean RDA for elderly people. Vitamin $B_2$ and folate intakes were significantly lower (p<0.l) in the risk group compared to the control group. The consumption of seaweed was significantly lower (p<0.05), and fish intake was 33% lower, in the risk group compared to the control group. Subjects in the risk group showed a higher BMI, waist/hip ratio, triceps skinfold thickness, and % body fat, compared to control subjects. Plasma triglyceride levels and values of the atherogenic index were significantly higher (p<0.00l) in risk group subjects. Significant negative correlations between HDL-cholesterol level and plasma triglyceride level (r= 0.37), and values of the atherogenic index (r=-0.74), were found. In summary, subjects with low levels of HDL-cholesterol were found to have relatively low intakes of vitamin B$_2$, folate, and seaweed, and higher levels of the CVD risk factors: body fat, plasma TG, and AI. These results suggest that plasma HDL-cholesterol levels can be modified by dietary, anthropometric, and hematological means.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1084-1089
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• 1990

Plasma protein concentration, plasma albumin concentration, hematocrit, and arterial blood gas tension were measured in 15 mongrel dogs undergoing heart transplantation with cardiopulmonary bypass. The hemodilution due to priming solution resulted in a 49% decrease in plasma protein concentration, a 57% decrease in plasma albumin concentration, a 46%a decrease in hematocrit. The measurements had returned to preperfusion values 1 hour after the end of cardiopulmonary bypass. The intraoperative changes in plasma protein and albumin concentration did not correlate with changes in alveolar-arterial oxygen tension gradients[D[A\ulcorner PO2]]. It is concluded that, in the absence of an increase in left atrial pressure, marked decrease in plasma protein concentration can be tolerated without the occurrence of pulmonary edema. And further study should be done to determine how to prepare an ideal priming solution.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.4
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• pp.84-91
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• 1994

A compact electron cyclotron resonance(ECR) plasma system composed of a microwave generator and a magnet coil was fabricated. A Langmuir single probe was used to investigate the plasma characteristics of the system through I-V measurements. The performance of the compact ECR plasma system was tested for the case of silicon etching reaction with $CF_{4}/O_{2}$(30%) mixed gas. Electron density and etch rate increased to maximum values and then decreased with increasing argon gas pressure, but electron temperature changed in the opposite way. The electron density and the electron temperature of argon gas plasma were 0.85${\times}~5.5{\times}10^{10}cm^{-3}$ and 4.5~6.0 eV, respectively, in the pressure range from $3{\times}10^{4}$ to 0.05Torr. The etch rate reached a maximum value at the position of 2.5cm from the bottom of plasma cavity. Etch rate uniformity was $\pm$6% across 6cm wafer. Anisotropic index was 0.75 at 1.5${\times}10^{-4}$Torr.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.504-508
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• 2002

The effects of fetal number (single or twin) on blood glucose and plasma NEFA during pregnancy and around parturition were studied on ten Alpine ${\times}$ Beetal crossbred goats in their first to third lactation. The animals were divided in-groups 1(carrying single fetus, n=4) and 2(twin fetus, n=6). The samples were drawn on day1 after estrus and then at 14 days interval (fortnight) for 10 fortnights. Around parturition the samples were taken on days -20, -15, -10, -5, -4, -3, -2, -1 prior to kidding and on day 0 and +1, +2, +3, +4, +5, +10, +15, +20 days post kidding. In twin bearing goats the blood glucose concentration continued to increase from 1st until 4th fortnight and thereafter gradually decline from 5th upto 8th fortnight. In single bearing goats there was increase in levels from 2nd upto 4th fortnight and thereafter it declined from 5th uptill 9th fortnight. The difference in sampling interval was highly significant (p<0.01) in both the groups. However the values were higher in single than in twin bearing goats. The plasma NEFA concentration was low in both the groups' upto 4th fortnight and thereafter it is continuously increased upto 9th fortnight. During prepartum period the blood glucose was higher in single than in twin bearing goats. The values were minimum on the day of kidding in both the groups. During postpartum period the values were significantly (p<0.01) higher in twin than in single fetus bearing goats. The plasma NEFA was significantly (p<0.05) higher in twin than in single fetus bearing goats. The blood glucose and plasma NEFA concentration can be used as index of nutritional status during pregnancy and around parturition in goats.

• The Journal of Advanced Prosthodontics
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• v.12 no.2
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• pp.75-82
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• 2020

PURPOSE. The aim of this study was to investigate the shear bond strength of luting cements used with implant retained restorations on to titanium specimens after different surface treatments. MATERIALS AND METHODS. One hundred twenty disc shaped specimens were used. They were divided into three groups considering the surface treatments (no treatment, sandblasting, and oxygen plasma treatment). Water contact angle of specimens were determined. The specimens were further divided into four subgroups (n=10) according to applied cement types: polycarboxylate cement (Adhesor Carbofine-AC), temporary zinc oxide free cement (Temporary CementZOC), non eugenol provisional cement for implant retained prosthesis (Premier Implant Cement-PI), and non eugenol acrylic-urethane polymer based provisional cement for implant luting (Cem Implant Cement-CI). Shear bond strength values were evaluated. Two-way ANOVA test and Regression analysis were used to statistical analyze the results. RESULTS. Overall shear bond strength values of luting cements defined in sandblasting groups were considerably higher than other surfaces (P<.05). The cements can be ranked as AC > CI > PI > ZOC according to shear bond strength values for all surface treatment groups (P<.05). Water contact angles of surface treatments (control, sandblasting, and plasma treatment group) were 76.17° ± 3.99, 110.45° ± 1.41, and 73.80° ± 4.79, respectively. Regression analysis revealed that correlation between the contact angle of different surfaces and shear bond strength was not strong (P>.05). CONCLUSION. The retentive strength findings of all luting cements were higher in sandblasting and oxygen plasma groups than in control groups. Oxygen plasma treatment can improve the adhesion ability of titanium surfaces without any mechanical damage to titanium structure.

• Restorative Dentistry and Endodontics
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• v.42 no.2
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• pp.125-133
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• 2017

Objectives: This study compared the effect of hexamethyldisiloxane (HMDSO) and ammonia ($NH_3$) plasmas on the bond strength of resin cement to fiber posts with conventional treatments. Materials and Methods: Sixty-five fiber posts were divided into 5 groups: Control (no surface treatment); $H_2O_2$ (24% hydrogen peroxide for 1 min); Blasting (blasting with aluminum oxide for 30 sec); $NH_3$ ($NH_3$ plasma treatment for 3 min); HMDSO (HMDSO plasma treatment for 15 min). After the treatments, the Ambar adhesive (FGM Dental Products) was applied to the post surface (n = 10). The fiber post was inserted into a silicon matrix that was filled with the conventional resin cement Allcem Core (FGM). Afterwards, the post/cement specimens were cut into discs and subjected to a push-out bond strength (POBS) test. Additionally, 3 posts in each group were evaluated using scanning electron microscopy. The POBS data were analyzed by one-way analysis of variance and the Tukey's honest significant difference post hoc test (${\alpha}=0.05$). Results: The Blasting and $NH_3$ groups showed the highest POBS values. The HMDSO group showed intermediate POBS values, whereas the Control and $H_2O_2$ groups showed the lowest POBS values. Conclusion: Blasting and $NH_3$ plasma treatments were associated with stronger bonding of the conventional resin cement Allcem to fiber posts, in a procedure in which the Ambar adhesive was used.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.5
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• pp.218-223
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• 2005

Impedance matching characteristics of planar type inductively coupled plasma sources are investigated utilizing the previously reported two-dimensional theory[1] of the anomalous skin effect. Two types of matching networks are considered, and the values of the circuit elements are expressed as functions of various reactor parameter. Also, two cases of perfect and imperfect matching conditions are considered and the functional dependence of the values of matching capacitance and reflection coefficient on the various reactor parameters are investigated using the present circuit model.