• Restorative Dentistry and Endodontics
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• v.23 no.2
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• pp.537-549
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• 1998

The purpose of this study was to evaluate the influence of root resection and retrograde cavity preparation methods on the apical leakage in endodontic surgery. To investigate the effect of various root resection and retrograde cavity preparation methods on the apical leakage, 71 roots of extracted human maxillary anterior teeth and 44 mesiobuccal roots of extracted human maxillary first molars were used. Root canals of the all the specimens were prepared with step-back technique and filled with gutta-percha by lateral condensation method. Three millimeters of each root was resected at a 45 degree angle or perpendicular to the long axis of the tooth according to the groups. Retrograde cavities were prepared with ultrasonic instruments or a slow-speed round bur, and occlusal access cavities were filled with zinc oxide eugenol cement. Three coats of clear nail polish were placed on the lateral and coronal surfaces of the specimens except the apical cut one millimeter. All the specimens were immerged in 2% methylene blue solution for 7 days in an incubator at $37^{\circ}C$. The teeth were dissolved in 14 ml of 35% nitric acid solution and the dye present within the root canal system was returned to solution. The leakage of dye was quantitatively measured via spectrophotometric method. The obtained data were analysed statistically using two-way ANOVA and Duncans Multiple Range Test. The results were as follows: 1. No statistically significant difference was observed between ultrasonic retrograde cavity preparation method and slow-speed round bur technique, without apical bevel (p>0.05). 2. Ultrasonic retrograde preparation method showed significantly less apical leakage than slow-speed round bur technique, with bevel (p<0.0001). 3. No statistically significant difference was found between beveled resected root surface and non-beveled resected root surface, with ultrasonic technique (p>0.05). 4. Non-beveled resected root surface showed significantly less apical leakage than beveled resected root surface, with slow-speed round bur technique (p<0.0001). 5. No statistically significant difference in apical leakage was found between the group of retrograde cavity prepared parallel to the long axis of the tooth and the group of one prepared perpendicular to the long axis of the tooth (p>0.05). 6. Regarding isthmus preparation, ultrasonic retrograde preparation method showed significantly less apical leakage than slow-speed round bur technique, in the mesiobuccal root of maxillary molar, without bevel (p<0.0001).

• Journal of Life Science
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• v.25 no.5
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• pp.523-532
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• 2015

A variety of previous pharmacological studies have suggested Liriope platyphylla (L. platyphylla) may exert beneficial biological effects on inflammation, diabetes, neurodegenerative disorder, obesity, constipation, and atopic dermatitis. In addition, hydrocolloid membranes (HCMs) have attracted attention in dermatological care, including in the treatment of scleroderma skin ulcers, cutaneous ulcers, permanent tympanic membrane perforations, pressure sores, and decubitus ulcers in the elderly. To investigate the therapeutic effects of HCM containing an aqueous extract of L. platyphylla (HCM-LP) on second-degree burn wounds, their physico-chemical properties were analyzed and the therapeutic effects were observed in SD rats after treatment with HCM-LP for 14 days. Significant declines in tensile strength (38.4%) and absorptiveness (46.3%), as well as an increase in surface roughness (38.1%) were detected in HCM-LP compared with that of HCM. In SD rats with burned skin, the wound diameter was shorter in the HCM-LP treated group than in the GZ group on post-surgical day 14, while the significant improvements in scar tissue reduction, epithelium regeneration, angiogenesis, and extracellular matrix deposition were observed in the HCM-LP-treated group during all experimental periods. Overall, these results suggest HCM-LP may accelerate the process of healing the burn injury skin of SD rats through the regulation of angiogenesis and connective tissue formation.

• Restorative Dentistry and Endodontics
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• v.30 no.3
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• pp.178-183
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• 2005

This study was done to evaluate whether vital bleaching agents could influence on the translucency of the bovine enamel. The anterior bovine teeth that were extracted one day before and without any gross discoloration were obtained and then were preserved in physiologic saline. 6 mm cylindrical tooth specimens were fabricated with diamond puncher perpendicularly on labial surface of bovine tooth. After embedded in transparent acrylic resin with labial surface being exposed, they were cut to a thickness of 1.2 mm with low speed diamond saw (Isomat, Buehler Co., Lake Bluff, IL, USA). They were smoothly ground to 1 mm thickness of enamel with sandpaper. 24 specimens were randomly divided into 3 groups and control group respectively. Opalescence (10% carbamide peroxide, Ultradent, South Jordan, USA), Rembrandt (10% carbamide peroxide, DenMat, USA) and Opalescence F (15% carbamide peroxide with fluoride, Ultradent, USA) were applied on labial sides of the bovine enamel for 7 days (bleaching agents were reapplied every 24 hours) and the opposite surface was contacted to cotton that soaked in distilled water. The control group was soaked in distilled water. Three stimulus value X, Y and Z were evaluated with colorimeter (Color ' Color Differencerneter, Model TC-6FX, Tokyo Denshoku Co., Japan) on the labial surface of all specimen three times on white and black background plate before the bleaching agents were applied and on 3rd, 5th and 7th day after applied. The degree of translucency was normally assessed by measuring the inverse property, opacity (contrast ratio). 10% Opalescence, 15% Opalescence-F, and control group showed no significant variation in the translucency of bovine enamel, However Rembrandt decreased the translucency of it (p < 0.01).

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.1
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• pp.51-60
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• 2000

The purpose of this study was to compare the microleakage at the interface of cast post and tooth according to the type of cement. Forty anterior teeth with single root were used. The teeth were cut 2 mm coronal from the cementoeamel junction and chamfer finish line was made on 1 mm coronal from the cementoeamel junction. After the routine endodontic treatment, post space was prepared using #5.5 Parapost drill to a depth of 7 mm. After the pick up impression, core building was made to 3 mm of clinical crown with burnout wax, then post and core was cast with nonprecious metal. The teeth were divided into four groups of ten each. In Group I, post and core were cemented with Fleck's(Zinc phosphate cement) In Group II, post and core were cemented with Fuji I(Glass ionomer cement) In Group III, post and core were cemented with Superbond C & B(Composite resin cement) In Group IV, post and core were cemented with Panavia 21(Composite resin cement) All cemented teeth were stored in normal saline at $37^{\circ}C$ for 7 days and thermocycled from $5^{\circ}C$ to $55^{\circ}C$ for 500 cycles with a dwell time of 30 seconds. After thermocycling, teeth were immersed in 1% Basic fuchsin dye for 48 hours. All 40 teeth were then embedded in the epoxy resin and cut buccolingually with a cutting instrument. The degree of penetration of dye at interface was graded on a scale of 0 to 4 using a stereomicroscope at 25 to 40 times magnification. Through the findings of this study, the following conclusion were obtained. 1. All the groups showed the microleakage at the interface of cast post core and tooth. 2. Group I showed the highest microleakage score among the groups with a significant difference(p<0.05). 3. Group II showed higher microleakage score than Group III and Group IV with a significant difference(p<0.05). 4. Group IV showed the lowest microleakage score but there were no significant difference with Group III(p>0.05).

• The Journal of Dong Guk Oriental Medicine
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• v.8 no.2
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• pp.131-154
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• 2000

Nan Jing(Difficult Classic), as a catechism, describes in detail and deeply the ideas in Nei Jing(Huangdi's Internal Classic). The description of Nan Jing is focused on basic theories including theories about some disease and is excellent in identification and analysis. The contents of Nan Jing are as follows: 1-23 Nan-pulse and pulse condition, 24~29 Nan-channels and collaterals, 30~47 Nan-viscera and bowels(Zang Fu organs), 48~61 Nan-disease, 62~68 Nan-acupuncture points, 69~91 Nan-acupuncture. Especially, diagnosis techniques in Nan Jing make 'Only method of cunkou pulse taking' that is a technique for feeling the pulse widely applied in these days in Oriental medicine clear. Thus, this book adjusts the theory of pulse and pulse condition given in 1~23 Nan of 'The Study of Nan Jing' in order to enhance an understanding about the theory of pulse and pulse condition. The text of 1~23 Nan about pulse lore centers on all pulse of human body interconnected each other and cunkou, both ends of the pulse, and contrasts regular pulse with irregular pulse. 1. 10 Nan describes the theory about five kinds of evils and hardness and softness, and unique pulse condition of each bowels. 2. 13 Nan explains that the relative difficulty of medical treatment is determined by the degree of balance or unbalance among three factors-colors, pulse and pulse condition, flesh shape. 3. 14 Nan divides pulse and pulse condition into slow pulse and rapid pulse, and explains separately abnormality, great loss of semen, death caused by slow pulse, and abnormality, great loss of semen, death caused by rapid pulse. 4. 15 Nan about taut pulse(弦), full pulse(鉤), floating pulse(毛), deep pulse(石脈) describes that pulse and pulse condition differs according to four seasons. Therefore, Nan Jing establishes clearly techniques of feeling the pulse in 'Only method of cunkou pulse taking(獨取寸口)' and advances the theory of Nei Jing. Futhermore, Nan Jing is more valuable in that it suggests unique theory different with Nei Jing.

• Korean Journal of Microbiology
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• v.52 no.1
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• pp.98-109
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• 2016

The study was aimed to investigate the mixing ratio of kiwi and persimmon juices for the production of good quality wine by Saccharomyces cerevisiae Y28. Firstly, the optimum condition of rapidase treatment for the kiwi and persimmon juices was established, thereafter various mixing ratio (10:0, 9:1, 8:2, 7:3, 6:4, 5:5) of kiwi and persimmon was investigated regarding physiochemical properties and flavor compounds of wine. As the result, the optimum conditions were obtained as 0.3% rapidase for 1 h in kiwi and 0.3% rapidase for 3 h in persimmon. According to higher ration of persimmon, the pH of wines increased from 3.69 to 3.77, while the acidity of wines decreased from 2.07% to 1.51% at 14 days fermentation. The ranges of brix and reducing sugar in wines were decreased which ranges around 9.6 to 8.8 and 6.07 to 6.90 g/L, respectively, after fermentation. Major organic acid in wines were identified as tartaric acid, malic acid, and citric acid. A small amount of free sugar such as sucrose and glucose were detected in wines, but fructose was completely absent. The soluble phenolic contents were decreased that ranges around 1.00 to 1.25 g/L, in contrast, browning degree were increased ranges around 0.212 to 0.412 after fermentation. The major flavor components were identified as ethyl acetate and hydrazine, and 1,1-dimethyl. Importantly, phenylethyl alcohol was detected from the all wines that have a typical rose like flavor. But sensory test results and preference of kiwi-persimmon (7:3) mixing wine was better than the other wines.

• Clinical and Experimental Pediatrics
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• v.45 no.10
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• pp.1213-1218
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• 2002

Purpose : Hydronephrosis constitutes a great portion of fetal anomalies screened by prenatal sonogram. The present authors made an attempt to access its natural courses through follow up neonatal hydronephrosis diagnosed by prenatal sonogram. Methods : The study was composed of 23 neonates(36 renal units) who were diagnosed with hydronephrosis through prenatal sonogram screening and confirmed 3-7 days after birth with sonographic evaluation at Kyung Hee University Hospital. The neonates were closely monitored for 12-24 months with renal sonogram, diuretic renogram, intravenous pyelography(IVP) and voiding cystoureterography(VCUG). Results : The underlying diseases were composed of 16 cases(44%) of functional abnormalities, 14 cases(39%) of ureteropelvic junction(UPJ) obstruction, three cases(8%) of vesicoureteral reflux (VUR) and on case each of multicystic dysplastic kidney, UPJ obstruction with ureteral stenosis and ureterovesical junction(UVJ) obstruction with VUR. The degree of hydronephrosis was divided into three classes according to its severity. In 30 renal units with UPJ obstruction and functional abnormalities, 26(87%) showed mild hydronephrosis, while four(13%) were moderate. During the follow up period, six cases(20%) showed natural resolution of hydronephrosis, 15 cases(50%) showed improvement while two cases(7%) were aggravated with improvement only after surgery of the underlying disease. The cases which showed natural resolution were all mild hydronephrosis at diagnosis and the cases which underwent surgery due to continuous aggravation were mild one case and moderate one case. Conclusion : Those with cases of mild hydronephrosis show rapid natural improvement. On the other hand, in some cases, follow up monitoring reveal aggravation of the situation, emphasizing the necessity for thorough follow up for a long period of time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.166-172
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• 2002

The top shell, Omphalius pfeifferi capenteri meat vacuum-packed in can (diameter$\times$height, 74.1mm$\times$50.7mm) were heated at 115$^{\circ}C$ up to $F_0$ values of 5 min, 10 min, 15 min and 20 min, and the changes in food components were studied. After 14 days storage at 37$^{\circ}C$ and 55$^{\circ}C$, no growth of microorganism and panelling were recognized from the canned meats which were sterlized at 115$^{\circ}C$ with $F_0$ value of S min and over. In the case of proximate composition of the canned meats, the moisture content decreased with the increase of $F_0$ value, while crude protein increased. The increase of volatile basic nitrogen content, pH and degree of browning and the decrease of mineral, total amino acid, free amino acid, trimethylamine oxide, total creatinine contents and yields were observed during thermal processing, In sensory evaluation on color, texture and taste in the canned meats, no significant difference was observed among a boiled sample and the canned meats heated at re value of 10 min and below. But, in the canned meats heated at $F_0$ value of over 15 min, its sensory scores decreased with the increase of $F_0$ value. From these results, the reasonable $F_0$ value for preparation of the heat-treated top shell meats was in the range of 5$\~$10 min.

• Korean Journal of Plant Resources
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• v.33 no.2
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• pp.80-85
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• 2020

A new Gomchwi cultivar 'Soomany' was derived from a cross between Gomchwi (Ligularia fischeri (Ledeb.) Turcz.) and Handaeri-gomchwi (Ligularia fischeri var. spiciformis Nakai). The investigation and selection of growth and yield characteristics were conducted from 2007 to 2015 in field and greenhouse of Highland Agriculture Research Institute, National Institute of Crop Science, Rural Development Administration, in Korea. On a newly developed cultivar 'Soomany', color of petiole ear is light green, petiole trichome is existent, trichome and light on the back of the leaves don't exist, and density of leaf vein is degree 4. Plant height, leaf length, leaf width and petiole length are 77.1, 22.3, 21.5 and 57.2 cm, respectively in the growth characteristics of the 2_nd year. Plant size was also higher than that of 'Sammany' generally. Bolting date was on August 15. Flowering date was on September 19, about 9 days later than 'Sammany'. 'Soomany' and 'Sammany' had 149 and 133 leaves per plant, respectively. Total yield of 'Soomany' (1,623 g/plant) made a very good comparison with that of 'Sammany' (1,385 g/plant). 'Soomany' showed harder leaves (25.8 ㎏/㎠) than 'Sammany' (20.8 ㎏/㎠), whereas 'Soomany' had thinner leaves (0.53 mm) than 'Sammany' (0.62 mm). 'Soomany' variety has shown strong resistance to powdery mildew disease compared to 'Sammany'. In May 2019, the right of variety protection of 'Soomany' was registered as a new Gomchwi variety (Register No. 192).

• Korean journal of applied entomology
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• v.50 no.3
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• pp.235-245
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• 2011

Temperature-related parameters of Panonychus citri (McGregor) (Acarina: Tetranychidae) development were estimated and a stage-structured matrix model was developed. The lower threshold temperatures were estimated as $8.4^{\circ}C$ for eggs, $9.9^{\circ}C$ for larvae, $9.2^{\circ}C$ for protonymphs, and $10.9^{\circ}C$ for deutonymphs. Thermal constants were 113.6, 29.1, 29.8, and 33.4 degree days for eggs, larvae, protonymphs, and deutonymphs, respectively. Non-linear development models were established for each stage of P. citri. In addition, temperature-dependent total fecundity, age-specific oviposition rate, and age-specific survival rate models were developed for the construction of an oviposition model. P. citri age was categorized into five stages to construct a matrix model: eggs, larvae, protonymphs, deutonymphs and adults. For the elements in the projection matrix, transition probabilities from an age class to the next age class or the probabilities of remaining in an age class were obtained from development rate function of each stage (age classes). Also, the fecundity coefficients of adult population were expressed as the products of adult longevity completion rate (1/longevity) by temperature-dependent total fecundity. To evaluate the predictability of the matrix model, model outputs were compared with actual field data in a cool early season and hot mid to late season in 2004. The model outputs closely matched the actual field patterns within 30 d after the model was run in both the early and mid to late seasons. Therefore, the developed matrix model can be used to estimate the population density of P. citri for a period of 30 d in citrus orchards.