• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.222-235
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• 2007

The objectives of this study was to evaluate the effect of thermocycling on the ${\mu}TBS$ (microtensile bond strength) to dentin with four different adhesive systems to examine the bonding durability. Freshly extracted $3^{rd}$ molar teeth were exposed occlusal dentin surfaces, and randomly distributed into 8 adhesive groups 3-steps total-etching (Scotchbond Multi-Purpose Plus; SM, All Bond-2; AB), 2-steps total-etching (Single Bond; SB, One Step plus; OS), 2-steps self-etching (Clearfil SE Bond; SE, AdheSE AD) and single-step self-etching systems (Promp L-Pop; PL, Xeno III; XE) Each adhesive system in 8 adhesives groups was applied on prepared dentin surface as an instruction and resin composite (Z250) was placed incrementally and light-cured. The bonded specimens were sectioned with low-speed diamond saw to obtain $1\times1mm$ sticks after 24 hours of storage at $37^{\circ}C$ distilled water and proceeded thermocycling at the pre-determined cycles of 0, 1,000 and 2,000. The ${\mu}TBS$ test was carried out with EZ-tester at 1mm/min. The results of bond strength test were statistically analyzed using one-way ANOVA/ Duncan's test at the a < 0.05 confidence level. Also, the fracture mode of debonded surface and the interface were examined under SEM. The results of this study were as follows ; 1. 3-step total etching adhesives showed stable, but bond strength of 2-step adhesives were decreased as thermocycling stress. 2. SE showed the highest bond strength, but single step adhesives (PL, XE) had the lowest value both before and after thermocycling. 3 Most of adhesives showed adhesive failure. The total-etching systems were prone to adhesive failure and the single-step systems were mixed failure after thermocycling. Within limited results of this study, the bond strength of adhesive system was material specific and the bonding durability was affected by the bonding step/ procedure of adhesive Simplified bonding procedures do not necessarily imply improved bonding performance.

• Journal of Chest Surgery
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• v.38 no.2 s.247
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• pp.110-115
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• 2005

Background: The aims of this paper were to review the mid term clinical results and to analyze the preoperative risk factors of isolated aortic valve replacement (AVR). Material and Method: Between January 1992 and February 2003, 80 patients underwent isolated AVR. 58 were male and 22 were female patients, raging from 12 to 75 years of age (mean :$46.8{\pm}13.0$ years). 74 patients except one early death and 5 follow-up loss were contacted by OPD or by telephone. The mean duration of follow-up was $44.2{\pm}29.7$ months and the total cumulative period was 272.8 patient-year. Result: The complications in hospital occurred in 35 cases : 12 wound problems (11 superficial, 1 deep), 11 arrhythmias (9 temporary, 2 persistent), 3 low cardiac output, and so forth. The late deaths were 4 cases : the heart-related deaths were 2 cases ($0.7\%$ patient-year). Conclusion: The risk factors that influenced the early mortality and morbidity were older age (> 60 years)(p=0.04), poor preoperative NYHA functional class (> 3) (p=0.048), high preoperative serum creatinin level (> 1.2 mg/100 ml)(p=0.031), long operation time (aortic clamping time>90 min)(p=0.042). The same factors influenced the late mortality and morbidity. Freedom from valve-related complication was $86.4{\pm}5.3\%,$ actuarial survival rate were $96.8{\pm}2.3\%$ at 3 years and $90.8{\pm}4.6\%$ at 10 years.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.293-299
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• 1986

Obstetric problems concerning macrosomia were evaluated by retrospective review of 91 pregancies that resulted in the delivery of an infant weighing 4,000gm or more at the Yeungnam University Hospital during 3 1/2 years from Jun. 1983 to Oct. 1986. The results obtained were as follows. 1. Macrosomic infants weighing 4.000gm or more occured in 2.8% of the deliveries. 2. 65.9% of macrosomic infants and 53.5% of total infants were male. The ratio of male was statistically higher in the macrosomic infants than in the total infants(P<0.05). 3. The incidence of macrosomia was higher with increasing qestational age, and deliveries at 42 weeks or more gestation were more common in the macrosomic infants than in the total infants(P<0.01). 4. The incidence of macrosomia was highter with increasing parity, and stastically higher in the multipara than in the primipara(P<0.01). 5. There was no difference in the incidence of macrosomia between the mothers aged 24 or less and that of 30 or more. 6. The cesarean section rate of macrosomia(30.8%) was stastically higher than that of the total infants(15.7%)(P<0.01) 7. With the pregnacy and delivery of macrosomic infants, 22 antepartum anemia(24.2%), 10 postpartum hemorrhage(11.0%), 9 birth canal injury(10.0%), 7 prolonged second stage of labor (7.7%), 4 breech presentation, and 3 pregancy induced hypertension occured in the mothers, and 10 asphyxia(or Apgar score 6 or less), 2 shoulder dystocia, 1 intrauterine fetal death, and 1 sacrococcygeal teratoma occured in the infants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.57-66
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• 2013

The purpose of this study was to investigate the effects of shifts in sowing time on the ecological responses, growth and yields of major soybean cultivars in a southern region of South Korea. Experiments were carried out in Naju, Jeonnam Province (latitude $35^{\circ}$ 04'N, longitude $126^{\circ}$ 54'E) for three years from 2008 to 2010. The test cultivars included Saeol-kong and Tawon-kong of the summer type, Taekwang-kong and Pungsannamul-kong, and Cheongja3 of the autumn type. Sowing took place on May 15 and 30, June 15 and 30, and July 15 of each year. Of the summer type soybean cultivars, Saeol-kong showed a smaller curtailment in days from sowing to flowering, days from flowering to maturity, and days from sowing to maturity according to sowing time postponement than Tawon-kong. Of the autumn type soybean cultivars, Taekwang-kong exhibited a lower photoperiodic response in reproductive growth period than Pungsannamul-kong and Cheongja3, both of which recorded higher level photoperiodic responses in vegetative growth stages and reproductive growth periods than other test cultivars, with the former exhibiting higher levels than the latter. Most of the test cultivars tended to decrease in stem length, node numbers of the main stem, and stem diameter according to postponed sowing time, but there were no significant differences in stem length and node numbers of the main stem of the Saeol-kong cultivar. Differences in sowing times did not affect the first setting pod node order of Saeol-kong and Tawon-kong summer type cultivars of internode lengths of all of the test cultivars. All of the test cultivars tended to show decreases in pod number per plant due to postponement of sowing time except for the Saeol-kong cultivar. The variation was more prominent in small grain cultivars such as Tawon-kong and Pungsannamul-kong with the latter autumn type cultivar showing especially large variation. Yields were the greatest for the Tawon-kong, Taekwang-kong, and Pungsannamul-kong cultivars sown on May 30 and Cheongja3 sown on May 30 and June 15. There were no significant differences in the yields of Saeol-kong for different sowing times from May 30 to July 15, with the yields lowest for the batch sown on May 15.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.2
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• pp.49-67
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• 2006

A mesocosm, an artificial tidal flat ecosystem, was constructed outdoors to simulate in situ physical and biochemical environmental conditions of natural tidal flat as much as possible. During the experiment from February to August 2004, the study was focused on the biogeochemical variations of superficial water and porewater after introduction of freshwater into the mesocosm. The mesocosm has three experimental conditions; SW-M-T: maintaining the saline water of approximately 20 psu; FW-M-T: complete exchange of freshwater ul the mesocosm with continuous mixing of water column: FW-NM-T: complete exchange of saline water to freshwater in the mesocosm without mixing of water column. Mass extinction of benthic macrofauna appeared due to drastic decrease of porewater salinity from 20 psu to less than 10 psu between the 63th and 91st day of freshwater introduction in FW-M-T and FW-NM-T. Throughout the periods, 7/8 of bivalves and 2/3 of polychaete populations have been extinguished in the sediment. In FW-NM-T, as temperature rises, both evident decrease of DO in water column and active release of DIP from sediment were observed. ${NO_3}^-$ was removed from water column into sediment throughout the periods. Therefore extremely low ${NO_3}^-$ was found during late spring and summer. Whereas ${NH_4}^+$ exhibited only $1/2{\sim}1/8$ of ${NO_3}^-$ concentration. Unexpectedly even after mass extinction of benthic macrofauna, we were not able to find high ${NH_4}^+$. This mesocosm study suggests that when fresh water introduce to natural tidal flat, its sediment activity functions as a potential source of DIP, but a sink of ${NO_3}^-$.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.214-223
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• 2013

BACKGROUND: This study focused on the development of an analytical method about dichlorprop (DCPP; 2-(2,4-dichlorophenoxy)propionic acid) which is a plant growth regulator, a synthetic auxin for agricultural commodities. DCPP prevents falling of fruits during their growth periods. However, the overdose of DCPP caused the unwanted maturing time and reduce the safe storage period. If we take fruits with exceeding maximum residue limits, it could be harmful. Therefore, this study presented the analytical method of DCPP in agricultural commodities for the nation-wide pesticide residues monitoring program of the Ministry of Food and Drug Safety. METHODS AND RESULTS: We adopted the analytical method for DCPP in agricultural commodities by gas chromatograph in cooperated with Electron Capture Detector(ECD). Sample extraction and purification by ion-associated partition method were applied, then quantitation was done by GC/ECD with DB-17, a moderate polarity column under the temperature-rising condition with nitrogen as a carrier gas and split-less mode. Standard calibration curve presented linearity with the correlation coefficient ($r^2$) > 0.9998, analysed from 0.1 to 2.0 mg/L concentration. Limit of quantitation in agricultural commodities represents 0.05 mg/kg, and average recoveries ranged from 78.8 to 102.2%. The repeatability of measurements expressed as coefficient of variation (CV %) was less than 9.5% in 0.05, 0.10, and 0.50 mg/kg. CONCLUSION(S): Our newly improved analytical method for DCPP residues in agricultural commodities was applicable to the nation-wide pesticide residues monitoring program with the acceptable level of sensitivity, repeatability and reproducibility.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.244-251
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• 1991

This study was undertaken to assess the effectiveness of magnesium-and boron-enriched complex fertilizer(CF, N-P$_2$O$_{5}$-K$_2$O-MgO-B$_2$O$_3$: 14-10-12-3-0.2) on the maintenance and management of hilly pasture. The effectiveness of CF was compared to those of some straight fertilizers (SF). This first part of the study was concerned with the soil chemical properties and the mutural balances of mineral nutrients in the soils of a mixed grass-clover and a pure grass swards. The results of a two-year field experiment are summarized as follows: 1. The Mg contents in the soils of the CF plots were higher than those of the SF plots. On the other hand, the Ca contents were higher in the SF plots than in the CF plots. The contents of Mg and Ca, and CEC, except K, in both the CF and SF plots were considerably below the optimum levels. At the normal application rate of NPK, the contents of available P$_2$O$_{5}$ were close to the optimum level in both the CF and SF plots. 2. The contents of exchangeable Mg were lower than the K contents in soils of all the plots. At the normal application rate of NPK, the Mg contents in the CF plots, but not in the SF plots, were close to the critical level for general crops (0.29me Mg/100g soil). The Mg contents in soils of all the plots, however, were considerably below the critical level for pasture forages and grazing cows (0.41me/100g). 3. Considering the desirable base saturation level of soil, the saturation levels of Ca and Mg were insufficient in both the CF and SF plots. The saturation levels of Mg in the CF plots, however, were relatively good compared with the SF plots. The equivalent ratios or Mg/K, Ca/Mg. Ca:Mg:K, and %Mg of CEC in soils were generally unfavorable in all the plots. These ratios of the CF plots, however, were relatively better than those of the SF plots. 4. Considering the contents of exchangeable Ca and Mg in soils, it is suggested that the application of slaked magnesium lime as a soil amelioration might be desirable for the fundamental increment of those contents at pasture establishment.

• Journal of Chest Surgery
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• v.29 no.8
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• pp.816-821
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• 1996

Lung transplantation is the established treatment for the end stage lung disedse find preservation of the organ is a major obstacle In performing lung transplantation. For solving this problem, we evaluated the histopathologic changes for various preservation solutions. Male mongrel dogs of similar size and weight (15∼20 kg) were used. The dog lungs were flushed with 4fl normal saline(group 1 'n:5): Modified Euro-Collins solution(group 2 n:5) and University of Wisconsin solution (group 3 : n=6), 60m11kg through a catheter placed in the main pulmonary artery aft r flushing of PGE 1 (20ng1kg). The lungs were preserved for 60 hours and measured dry and wet weights. Histologic specimens were taken every 6 hours and %toed for light microscopic evaluation. The edema ratio of the lungs peaked in 12 hours although there was no difference between the groups. Histologically, alveolar septal changes developed in one case (20%) after 1 hour preservation with normal saline. In case of the University of Wisconsin solution, the alveolar septal distortions and swellings were seen in 1 cases (20%) after 6 hours preservation compared with 3 cases (60%) after 6 hours preservation with Modified Euro-Collins solution. Changes of the pneumocytes were observed after 24 hours preser- vation in group 1, after 48 hours preservation in group 2 and after 60 hours preservation in group 3. We conclude that University of Wisconsin solution might have a superior preservation effect compare to normal saline and Modified Euro-Collins solutions.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.212-218
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• 1986

Proteins in Korean rapeseeds, as in many other plantseeds, are usually bound to phytate molecules. These phytate-bound proteins are of little value as foodstuffs because of their poor solubility in digestive systems. Therefore it is necessary to remove phytates from proteins in order to convert these proteins io a useful foodstuff. In the work, an efficient procedure for removal of phytates from defatted Korean rapeseed was found. The influence of pH on the solubility of protein and phytate of rapeseed flour showed that the former was the lowest at pH 5.0 and began to increase as pH further raised. Meanwhile, the latter was the highest at pH 6.0, however, it was decreased abruptly at alkaline pH, especially to content of 1.3% at pH 11.5. The solubility cf protein was relatively high in NaCl aqueous solution at $pH\;6.0{\sim}8.0$, and did not male any noticeable difference depending on NaCl concentration. On the other hand, the solubility of phytate was high at pH of below 6.0 showing an abrupt decrease at pH of above 6.0. The solubility of protein in $CaCl_2$ aqueous solution was highest at $pH\;6.0{\sim}8.0$, however, there was no significant change at the whole range of tested pH of the solution. A maximum solubility of phytate was shown at $pH\;3.0{\sim}4.0$. And it was decreased abruptly at a higher pH of the above range and also decreased at a lower pH with higher $CaCl_2$ concentration. The solubility of phytate in $Na_2SO_3$ aqueous solution was highest at $pH\;5.0{\sim}8.0$. As the concentration goes up the maximum value of solubility was found to move to higher pHs. Depending on the concentration of $Na_2SO_3$, the decreasing pattern was changed in an alkaline solution. The solubility of phytate in the solution containing low concentration of $Ca^{2+}$ ion was low in all treatments at pH of above 7.0 and showed the maximum value at low pH as $Ca^{2+}$ ion concentration increases. The solubility of protein at pH 11.5 showed the highest value in $1mM\;Ca^{2+}$ ion solution.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.327-332
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• 2008

This study was conducted to evaluate the effects of dietary Bacillus subtilis on meat quality, growth performance and fecal malodor gas emission in finishing pigs. Thirty-six pigs (Landrace ${\times}$ Yorkshire ${\times}$ Duroc, $83.53{\pm}1.01\;kg$ average initial body weight) were used in a 35 d growth assay. Dietary treatments were 1) CON (basal diet), 2) B1 (basal diet + B. subtilis 0.1%) and 3) B2 (basal diet + B. subtilis 0.2%). The pigs were distributed into four pigs per pen with three replicate pens per treatments by completely randomized design. For the entire period, the final weight, ADO, ADFI and gain/feed were not significantly different among the treatments. There were no significant differences in meat quality (sensory evalution, meat color, TBARS, water holding capacity, drip loss, cooking loss and M. longissimus dorsi area) among the treatments. $H_2S$ was significantly decreased in B2 treatment compared to CON and B1 treatments (p<0.05). However, ammonia, mercaptans and acetic acid were not significantly different among the treatments. In conclusion, B. subtilis 0.2% treatments decreased fecal $H_2S$ gas emission in finishing pigs.