• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.432-461
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• 1995

The basic principles in the design of Class II amalgam cavity preparations have been modified but not changed in essence over the last 90 years. The early essential principle was "extension for prevention". Most of the modifications have served to reduce the extent of preparation and, thus, increase the conservation of sound tooth structure. A more recent concept relating to conservative Class II cavity preparations involves elimination of occlusal preparation if no carious lesion exists in this area. To evaluate the ideal ClassII cavity preparation design, if carious lesion exists only in the interproximal area, three cavity design conditions were studied: Rodda's conventional cavity, simple proximal box cavity and proximal box cavity with retention grooves. In this study, MO amalgam cavity was prepared on maxillary first premolar. Three dimensional finite element models were made by serial photographic method. Linear, eight and six-nodal, isoparametric brick elements were used for the three dimensional finite element model. The periodontal ligament and alveolar bone surrounding the tooth were excluded in these models. Three types model(B option, Gap option and R option model) were developed. B option model was assumed perfect bonding between the restoration and cavty wall. Gap option model(Gap distance: $2{\mu}m$) was assumed the possibility of play at the interface simulated the lack of real bonding between the amalgam and cavity wall (enamel and dentin). R option model was assumed non-connection between the restoration and cavty wall. A load of 500N was applied vertically at the first node from the lingual slope of the buccal cusp tip. This study analysed the displacement, 1 and 2 direction normal stress and strain with FEM software ABAQUS Version 5.2 and hardware IRIS 4D/310 VGX Work-station. The results were as followed. 1. Rodda's cavity form model showed greater amount of displacement with other two models. 2. The stress and strain were increased on the distal marginal ridge and buccopulpal line angle in Rodda's cavity form model. 3. The stress and strain were increased on the central groove and a part of distal marginal ridge in simple proximal box model and proximal box model with retention grooves. 4. With Gap option, Rodda's cavity form model showed the greatest amount of the stress on distal marginal ridge followed by proximal box model with retention grooves and simple proximal box model in descending order. 5. With Gap option, simple proximal box model showed greater amount of stress on the central groove with proximal box model with retention grooves. 6. Retention grooves in the proximal box played the role of supporting the restorations opposing to loads.

• Journal of radiological science and technology
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• v.35 no.2
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• pp.109-117
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• 2012

The purpose of this work was to evaluate an amorphous silicon cesium iodide based indirect flat-panel detector (FPD) in terms of their modulation transfer function (MTF), Wiener spectrum (WS, or noise power spectrum, NPS), and detective quantum efficiency (DQE). Measurements were made on flat-panel detector using the International Electrotechnical Commission (IEC) defined RQA3, RQA5, RQA7, and RQA9 radiographic technique. The MTFs of the systems were measured using an edge method. The WS(NPS) of the systems were determined for a range of exposure levels by two-dimensional (2D). Fourier analysis of uniformly exposed radiographs. The DQEs were assessed from the measured MTF, WS(NPS), exposure, and estimated ideal signal-to-noise ratios. Characteristic curve in the RQA3 showed difference in the characteristic curve from RQA5, RQA7, RQA9. MTFs were not differences according to x-ray beam quality. WS(NPS) was reduced with increasing dose, and RQA 3, RQA5, RQA7, RQA9 as the order is reduced. DQE represented the best in the 1mR, RQA 3, RQA5, RQA7, RQA9 decrease in the order. The physical imaging characteristics of FPD may also differ from input beam quality. This study gives an initial motivation that the physical imaging characteristics of FPD is an important issue for the right use of digital radiography system.

• Animal Bioscience
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• v.35 no.10
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• pp.1479-1488
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• 2022

Objective: This work was to determine coat inheritance and evaluate production performance for crossbred pigs from Berkshire×Chenghua (BC) compared with Chinese indigenous Chenghua (CH) pigs. Methods: The coat color phenotypes were recorded for more than 16,000 pigs, and the genotypes of melanocortin 1 receptor (MCIR) gene were identified by sequencing. The reproductive performance of 927 crossbred BC F4 gilts and 320 purebred CH gilts was recorded. Sixty pigs of each breed were randomly selected at approximately 60 days of age to determine growth performance during fattening period, which lasted for 150 days for BC pigs and 240 days for CH pigs. At the end of the fattening period, 30 pigs of each breed were slaughtered to determine carcass composition and meat quality. Results: The coat color of BC pigs exhibits a "dominant black" hereditary pattern, and all piglets derived from boars or sows genotyped E^D1 E^D1 homozygous for MC1R gene showed a uniform black coat phenotype. The BC F4 gilts displayed a good reproductive performance, showing a higher litter and tear size and were heavier at farrowing litter and at weaning litter than the CH gilts, but they reached puberty later than the CH gilts. BC F4 pigs exhibited improved growth and carcass characteristics with a higher average daily live weight gain, lower feed-to-gain ratio, and higher carcass lean meat rate than CH pigs. Like CH pigs, BC F4 pigs produced superior meat-quality characteristics, showing ideal pH and meat-color values, high intramuscular fat content and water-holding capacity, and acceptable muscle-fiber parameters. C18:1, C16:0, C18:0, and C18:2 were the main fatty acids in M. longissimus lumborum in the two breeds, and a remarkably high polyunsaturated/saturated fatty acid ratio of ~0.39 was observed in the BC F4 pigs. Conclusion: The BC F4 pigs exhibit a uniform black coat pattern and acceptable total production performance.

• Development and Reproduction
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• v.4 no.1
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• pp.115-123
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• 2000

A few enzymeimmunoassay (EfA) for testosterone (T) have been reported but was not suitable for all biological samples. The present study was designed to develop a rapid, ultrasensitive EIA and to apply this technique for study the physiological changes of T in biological samples. Saliva samples were collected at 06:00～09:00 hour during one menstrual cycle from 18 normally menstruating women and on 09:00～10:00 hour from 20 normal men. The present study shows an established EIA for testosterone, using horseradish peroxidase (HRP), which was covalently bonded to testosterone-3-carboxymethyloxime (T-3-CMO). One batch of T-antisera was also covalently linked to microcrystalline cellulose particles by a mixed anhydride method in order to facilitate separation of bound and free steroids. The established EIA was validated in terms of sensitivity, accuracy, specificity, precisions etc., comparing with conventional radioimmunoassay. The sensitivity of the established EIA was less than 25 pg/tube. The correlation coefficients between the expected T-values and observed T-values measured by EIA or RIA were r=0.985 and r=0.941 respectively. The cross reactivity of antiserum in EIA was a little higher than that of RIA, especially by 5 ${\alpha}$-DHT. The intra- and inter-assay precisions of the present EIA were similar to those of RIA. The present study also demonstrates that the normal T-values in saliva of Korean male ＆ female samples are 265.65${\pm}$15.80 pmol／l and 109.74${\pm}$ 12.01 pmol／l, respectively. The present EIA seems to be established and suitable for use in the endocrinological studies. The advantages of this EIA system also might make the present T-EIA an ideal procedure for use in a routine assay of ordinary laboratory with a conventional spectrophotometer.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.51-54
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• 2018

Purpose $^{18}F-THK5351$ is the newly developed PET probe for tau imaging in alzheimer's disease. The purpose of study was to establish the automated production of $^{18}F-THK5351$ on a commercial module. Materials and Methods Two different approaches were evaluated for the synthesis of $^{18}F-THK5351$. The first approach (method I) included the nucleophilic $^{18}F$-fluorination of the tosylate precursor, subsequently followed by pre-HPLC purification of crude reaction mixture with SPE cartridge. In the second approach (method II), the crude reaction mixture was directly introduced to a semi-preparative HPLC without SPE purification. The radiosynthesis of $^{18}F-THK5351$ was performed on a commercial GE $TRACERlab^{TM}$ $FX-_{FN}$ module. Quality control of $^{18}F-THK5351$ was carried out to meet the criteria guidelined in USP for PET radiopharmaceuticals. Results The overall radiochemical yield of method I was $23.8{\pm}1.9%$ (n=4) as the decay-corrected yield (end of synthesis, EOS) and the total synthesis time was $75{\pm}3min$. The radiochemical yield of method II was $31.9{\pm}6.7%$ (decay-corrected, n=10) and the total preparation time was $70{\pm}2min$. The radiochemical purity was>98%. Conclusion This study shows that method II provides higher radiochemical yield and shorter production time compared to the pre-SPE purification described in method I. The $^{18}F-THK5351$ synthesis by method II will be ideal for routine clinical application, considering short physical half-life of fluorine-18 ($t_{1/2}=110min$).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1082-1090
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• 2009

Peak expiratory flow rate(PEF) is a very important diagnostic parameter obtained from the forced vital capacity(FVC) test. The expiratory flow rate increases during the short initial time period and may cause measurement error in PEF particularly due to non-ideal dynamic characteristic of the transducer. The present study evaluated the initial rise slope($S_r$) on the flow rate signal to compensate the transducer output data. The 26 standard signals recommended by the American Thoracic Society(ATS) were generated and flown through the velocity-type respiratory air flow transducer with simultaneously acquiring the transducer output signal. Most PEF and the corresponding output($N_{PEF}$) were well fitted into a quadratic equation with a high enough correlation coefficient of 0.9997. But only two(ATS#2 and 26) signals resulted significant deviation of $N_{PEF}$ with relative errors>10%. The relationship between the relative error in $N_{PEF}$ and $S_r$ was found to be linear, based on which $N_{PEF}$ data were compensated. As a result, the 99% confidence interval of PEF error was turned out to be approximately 2.5%, which was less than a quarter of the upper limit of 10% recommended by ATS. Therefore, the present compensation technique was proved to be very accurate, complying the international standards of ATS, which would be useful to calibrate respiratory air flow transducers.

• Economic and Environmental Geology
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• v.26 no.2
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• pp.129-134
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• 1993

At the Janggun mine, boulangerite usually occurs as needles or irregularly-shaped grains, up to $500{{\mu}m}$ in longer dimensions, closely associated with galena, minerals of a tetrahedrite-freibergite series and bournonite in the peripheries of South A and B orebodies and the zone of manganoan carbonates surrounding them. In some places, especially at the top of South B orebody, it occures as "feather ore" consisting of its fine needles or "hairs" in small drusy cavities together with fine-grained euhedral galena, pyrite, manganoan carbonates, quartz, etc. In reflected light, it is bluish grey in colour exhibiting moderate bireflectance and is strongly anisotropic without any internal reflections. Reflectance in air is $R_{max}=43.2$, $R_{min}=35.7$ percent at wavelength of 580 nm, and VHN: $146-173\;kg/mm^2$ at a 50 g-load. The chemical composition on the average from 23 complete spot analyses by electron microprobe is, Pb 56.1, Sb 25.1, S 18.5, Total 99.6 (all in weight percent); the corresponding chemical formula calculated on the basis of S=11 is; $Pb_{5.16}Sb_{3.93}S_{11.0}$ which fulfils approximately the ideal formula $Pb_5Sb_4S_{11}$. The strongest reflections on the X-ray diffraction pattern are; $3.73\;{\AA}\;(10)$, $3.22\;{\AA}\;(5)$, $3.03\;{\AA}\;(4)$ and $2.82\;{\AA}\;(5)$ and the pattern is in harmonic with space group $C^5_{2h}-P2_1/a$. From the textural evidence of the microscopic observations, the mineral is considered to have been formed at the latest stage of hydrothermal lead-zinc-silver mineralization.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.918-926
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• 2008

It is well known non-drug therapy for hypertension patients can reduce blood pressure. These types of therapy include maintaining ones ideal body weight, quitting smoking, consuming large amounts of fruits and vegetables consuming low levels of saturated fat and salt and regular exercise. Fermented milk protein derived biologically active peptides such as isoleucine-proline-proline_(IPP) or valine-proline-proline_(VPP) have been shown to lower blood pressure in hypertensive subjects. This study was conducted to investigate the antihypertensive effects of medical nutritional therapy _(MNT) in accordance with the consumption of fermented milk enriched with IPP and VPP. To accomplish this, we conducted a randomized case-controlled study of 43 subjects who had blood pressure levels greater than 120/80 mmHg. The subjects in the study group were randomly allocated into two groups, an MNT + fermented milk (100mL/day) group (n=21) and an MNT+L. helveticus fermented milk with tripeptides (IPP=2.2mg, VPP=2.6mg/100mL) group (n=22). The MNT included weight management, reduction of sodium, total fat and saturated fat intake, increased intake of fruits and vegetables, and increased intake of low fat dairy products. The treatments were administered for 12 weeks during which time no drug interventions were conducted. The daily intakes of total calories, fats, cholesterol and Na decreased significantly after 12 weeks of MNT in the control and the experimental groups. In addition, the systolic blood pressure de creased significantly in the control and experimental groups; however, the diastolic blood pressure only decreased significantly in the experimental group. Overall, the results of this study indicate that the intake of fermented milk containing IPP and VPP in conjunction with MNT exerted positive effects on the blood pressure of pre- and hypertensive subjects.

• Food Science and Preservation
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• v.30 no.5
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• pp.857-867
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• 2023

In this study, the extraction yield, acidic polysaccharides and ginsenosides of red and black ginseng were optimized by using the response surface methodology in consideration of the ethanol concentration and temperature of the extraction. The R² of the model formula for the yield, acidic polysaccharides and ginsenosides was 0.8378-0.9679 (p<0.1). An optimal extraction yield of 5.29% was reached for red ginseng soluble solids when 1.52% ethanol concentration was used at a temperature of 67.27℃. Additionally, the optimal extraction yield for black ginseng soluble solid was 6.11% when 3.12% ethanol concentration was used at a temperature of 66.13℃. Furthermore, the optimal conditions for extracting acidic polysaccharides from red ginseng were using an ethanol concentration of 4.03% at a temperature of 69.61℃; a yield of 1.86 mg/mL was obtained. The optimal extraction yield for acidic polysaccharides from black ginseng was 1.80 mg/mL when extracted using a concentration of 24.67% of ethanol at a temperature of 71.14℃. An optimal extraction yield of 0.22 mg/mL was reached for ginsenoside Rg₁ from red ginseng when 79.92% ethanol concentration was used at a temperature of 70.62℃. The optimal extraction yield of ginsenoside Rg₃ from black ginseng was 0.31 mg/mL when ethanol was used at a concentration of 75.70% at a temperature of 65.49℃. The ideal extraction conditions for obtaining the maximum yield of both acidic polysaccharide and ginsenoside from red and black ginseng were using ethanol at a concentration between 35 and 50% at an extraction temperature of 70℃.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.115-118
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• 2012

Purpose: The Levey-Jennings chart controlled measurement values that deviated from the tolerance value (mean ${\pm}2SD$ or ${\pm}3SD$). On the other hand, the upgraded Westgard Multi-Rules are actively recommended as a more efficient, specialized form of hospital certification in relation to Internal Quality Control. To apply Westgard Multi-Rules in quality control, credible quality control substance and target value are required. However, as physical examinations commonly use quality control substances provided within the test kit, there are many difficulties presented in the calculation of target value in relation to frequent changes in concentration value and insufficient credibility of quality control substance. This study attempts to improve the professionalism and credibility of quality control by applying Westgard Multi-Rules and calculating credible target value by using a commercialized quality control substance. Materials and Methods : This study used Immunoassay Plus Control Level 1, 2, 3 of Company B as the quality control substance of Total T3, which is the thyroid test implemented at the relevant hospital. Target value was established as the mean value of 295 cases collected for 1 month, excluding values that deviated from ${\pm}2SD$. The hospital quality control calculation program was used to enter target value. 12s, 22s, 13s, 2 of 32s, R4s, 41s, $10\bar{x}$, 7T of Westgard Multi-Rules were applied in the Total T3 experiment, which was conducted 194 times for 20 days in August. Based on the applied rules, this study classified data into random error and systemic error for analysis. Results: Quality control substances 1, 2, and 3 were each established as 84.2 ng/$dl$, 156.7 ng/$dl$, 242.4 ng/$dl$ for target values of Total T3, with the standard deviation established as 11.22 ng/$dl$, 14.52 ng/$dl$, 14.52 ng/$dl$ respectively. According to error type analysis achieved after applying Westgard Multi-Rules based on established target values, the following results were obtained for Random error, 12s was analyzed 48 times, 13s was analyzed 13 times, R4s was analyzed 6 times, for Systemic error, 22s was analyzed 10 times, 41s was analyzed 11 times, 2 of 32s was analyzed 17 times, $10\bar{x}$ was analyzed 10 times, and 7T was not applied. For uncontrollable Random error types, the entire experimental process was rechecked and greater emphasis was placed on re-testing. For controllable Systemic error types, this study searched the cause of error, recorded the relevant cause in the action form and reported the information to the Internal Quality Control committee if necessary. Conclusions : This study applied Westgard Multi-Rules by using commercialized substance as quality control substance and establishing target values. In result, precise analysis of Random error and Systemic error was achieved through the analysis of 12s, 22s, 13s, 2 of 32s, R4s, 41s, $10\bar{x}$, 7T rules. Furthermore, ideal quality control was achieved through analysis conducted on all data presented within the range of ${\pm}3SD$. In this regard, it can be said that the quality control method formed based on the systematic application of Westgard Multi-Rules is more effective than the Levey-Jennings chart and can maximize error detection.