• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.446-454
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• 2021

Critical heat flux (CHF) has traditionally been evaluated using look-up tables or empirical correlations for nuclear power plants. However, under complex moving condition, it is necessary to reconsider the CHF characteristics since the conventional CHF prediction methods would no longer be applicable. In this paper, the additional forces caused by motions have been added to the annular film dryout (AFD) mechanistic model to investigate the effect of moving condition on CHF. Moreover, a theoretical model of the natural circulation loop with additional forces is established to reflect the natural circulation characteristics of the loop system. By coupling the system loop with the AFD mechanistic model, a CHF prediction program called NACOM for natural circulation loop under moving condition is developed. The effects of three operating conditions, namely stationary, inclination and rolling, on the CHF of the loop are then analyzed. It can be clearly seen that the moving condition has an adverse effect on the CHF in the natural circulation system. For the calculation parameters in this paper, the CHF can be reduced by 25% compared with the static value, which indicates that it is important to consider the effects of moving condition to retain adequate safety margin in subsequent thermal-hydraulic designs.

• Imaging Science in Dentistry
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• v.48 no.4
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• pp.269-275
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• 2018

Purpose: The aim of this study was to evaluate the correlations between measurements made using panoramic radiography and cone-beam computed tomography (CBCT) based on certain anatomical landmarks of the jaws, with the goal of preventing complications due to inaccurate measurements in the pre-surgical planning phase of dental implant placement. Materials and Methods: A total of 56 individuals who underwent panoramic radiography and a CBCT evaluation before dental implant surgery were enrolled in the study. Measurements were performed to identify the shortest vertical distance between the alveolar crest and neighboring anatomical structures, including the maxillary sinus, nasal floor, mandibular canal, and foramen mentale. The differences between the measurements on panoramic radiography and CBCT images were statistically analyzed. Results: Statistically significant differences were observed between the measurements on panoramic radiography and CBCT for all anatomical structures (P<.05). The correlation coefficients (r) between the paired samples obtained from panoramic radiography and CBCT were closely correlated (P<.05), with r values varying from 0.921 and 0.979 for different anatomical regions. Conclusion: The results of this study support the idea that panoramic radiography might provide sufficient information on bone height for preoperative implant planning in routine cases or when CBCT is unavailable. However, an additional CBCT evaluation might be helpful in cases where a safety margin cannot be respected due to insufficient bone height.

• The Korean Journal of Pain
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• v.13 no.2
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• pp.182-186
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• 2000

Background: Ropivacaine is a new amide local anesthetics, having therapeutic properties similar to those of bupivacaine but less cardiovascular toxicity and motor blockade. The aim of this study was to evaluate the effects of ropivacaine used in stellate ganglion block (SGB) compared with those of lidocaine or bupivacaine. Methods: This prospective and crossover study performed in twenty patients with sudden sensory neural hearing loss. All patients received three times SGB, in the paratracheal approach using 8 ml of 1% lidocaine, 0.2% bupivacaine, and 0.2% ropivacaine respectively without any orders. Onset time and action duration of Horner's syndrome were observed after each SGB. Results: Onset time of ropivacaine was the middle of the three agents; earlier lidocaine and slower bupivacaine. Lidocaine ($3.0{\pm}1.9$ min), bupivacaine ($4.1{\pm}2.9$ min) and ropivacaine ($3.3{\pm}1.3$ min). But there were no significant differences; Action duration of Horner's syndrome of ropivacaine (223.6?105.2 min) was longer than lidocaine ($134.6{\pm}77.3$ min) and shorter than bupivacaine ($241.2{\pm}115.8$ min). There were significant differences in the action duration of each local anesthetics (P<0.05). There was no critical side effects and temporary foreign body sensation was the most common side effect. Conclusions: We conclude that ropivacaine is a good alternative in SGB instead of lidocaine or bupivacaine. Ropivacaine is a long acting local anesthetic similar to those of bupivacaine with wide margin of safety. However, optimal concentration and volume of ropivacaine in SGB should be studied.

• The Journal of Fisheries Business Administration
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• v.52 no.4
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• pp.29-43
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• 2021

This study investigated whether there is a correlation between the occurrence of hazardous substances such as vibrio, norovirus, radioactivity, shellfish posion, hepatitis A, etc. and media reports, and whether the occurrence of hazardous substances and media reports affect the production, distribution and consumption of aquatic products. The main research results are as follows. First, it can be seen that there is a difference in the relationship between the occurrence of hazardous substances and media reports according to hazardous substances. Second, it suggests seen that the occurrence of hazardous substances and media reports can have a negative effect on the production and the prices of aquatic products. Third, it was found that the occurrence and reporting of hazardous substances had different effects on the distribution margin of aquatic products due to the complexity and rigidity of the distribution structure. Fourth, consumers feel a threat to aquatic products safety and significantly reduce consumption when hazardous substances occur. There is a possibility that concerns about one item may lead to a decrease in consumption of domestic and imported aquatic products that are not related at all to the occurrence of hazardous substances. In conclusion, aquatic products are exposed to various hazardous substances such as vibrio, norovirus, radioactivity, shellfish posion, and hepatitis A. It was found that the occurrence of hazardous substances and its media reports could cause damage to the fishery sector.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.430-440
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• 2001

Orally administered chloral hydrate is often used, because of it's wide margin of safety and relatively few sideeffects. Hydroxyzine is an antihistamine with sedative and anti-emetic properties. It has been used in conjunction with chloral hydrate to reduce the incidence of nausea and vomiting. But, it's therapeutic drug concentration has not been established. The purpose of this study was to assess the sedative effect and physiologic parameter of hydroxyzine of different doses in sedating young pediatric dental patients. Fifty uncooperative children, mean age 33.2 months, who needed at least four separate restorative visits, requiring local anesthesia participated in this study. On every visit, one of the following 4 different sedative regimen was given (1) 70mg/kg CH (2) 70mg/kg CH and 1mg/kg HD (3) 70mg/kg CH and 2mg/kg HD (4) 70mg/kg CH and 3mg/kg HD. Physiologic parameter was recorded and behavior was videotaped and rated using Ohio State University Behavior Rating Scale by one investigator, blind to the dose. The analyzed sedative effect of combined oral administration of 70mg/kg chloral hydrate and 2mg/kg hydroxyzine was superior to the other regimens. Evidence of adverse effect was not detected or reported during and/or after the procedures.

• Archives of Plastic Surgery
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• v.38 no.2
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• pp.212-216
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• 2011

Purpose: Ameloblastomas are rare benign tumors of odontogenic origin, and compose about 1% of all oral and maxillomandibular cysts and tumors. Because this neoplasm has a high rate of local recurrence, segmental mandibulectomy with a 1~2 cm safety margin and immediate microsurgical reconstruction is an accepted treatment modality. The authors experienced four mandibular reconstruction cases that underwent secondary dental implantation. Here, the authors describe these cases and their long-term results. Methods: Four patients with ameloblastoma of the mandible underwent segmental mandibulectomy and reconstruction with a free fibula osseous flap from January 1999 to May 2005, followed by secondary dental implantation. Recurrence, bony union, implant osseointegration, and functional and aesthetic results were evaluated by radiologic imaging, by physical examination, and by using photographs. Results: All free flaps survived with no evidence of flap loss. To date, no recurrence has been noted clinically or radiologically. Imaging after mandibular reconstruction with a free fibular flap revealed satisfactory bony unions and mandibular contours. The patients achieved good aesthetic and functional results after the secondary implantation. Conclusion: Mandibular reconstruction using a fibular osseous flap and secondary dental implantation can produce good functional and aesthetic results after segmental mandibulectomy for ameloblastoma.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.215-223
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• 2012

The principal objective of this study was to evaluate the consumption behavior of housewives in the Jeonju area with respect to their use of environmentally-friendly agricultural products(EAPs) and to assess the need for EAPs in childcare centers also in the Jeonju area. Self-administered questionnaires were given to and collected from 278 housewives 42.4% of whom employed and 57.6% were unemployed. Statistical data analysis was performed on the data collected using SPSS v. 12.0. The average score of awareness about EAPs was $3.57{\pm}0.56$. The percentage of subjects who purchased EAPS was 76.3% regularly. On this group, 40.3% purchased EAPs 1~2 times in week. Unemployed housewives purchased more than employed housewives by a statistically significant margin(p<0.05). The most-purchased EAPs were vegetables. The average satisfaction score that housewives reported in relation to foodservice provided in childcare centers was $3.66{\pm}0.58$. About 65% of the respondents felt that the EAPs-foodservice in childcare centers was an important factor for them in choosing of a childcare centers. Approximately 42% of the housewives responded that EAPs-foodservice in childcare centers was needed to improve the safety of foodservice provided in chidcare centers. The percentage of subjects who wanted to expand EAPs-foodservice in childcare centers even though the parents would have to bear some of the financial burden was 42.5%. A higher proportion of employed housewives wanted to expand EAPs-foodservice in childcare centers more than unemployed housewives, and this finding was statistically significant(p<0.05).

• Toxicological Research
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• v.35 no.2
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• pp.131-136
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• 2019

Ethylhexyl dimethyl para-aminobenzoic acid (PABA) is an oily yellow liquid derivative of water-soluble PABA commonly used in sunscreen. Ethylhexyl dimethyl PABA is widely used as an ingredient in many cosmetics at an average concentration of 1.25% (0.5-2.0%) in Korea. Previous studies, including those involving animals, have demonstrated that ethylhexyl dimethyl PABA is toxic to the following four organs: testis, epididymis, spleen, and liver. In addition, experiments using human keratinocytes found that ethylhexyl dimethyl PABA inhibits cell growth and DNA synthesis at low concentrations, and halted the cell cycle of MM96L cells (human melanoma cell line) at the G1 phase. Despite limited clinical data in humans, many studies have confirmed increased mutagenicity of ethylhexyl dimethyl PABA following exposure to sunlight, which suggests that this molecule is likely to contribute to onset of sun-induced cancer despite protecting the skin through absorption of UVB. For risk assessment, the no observed adverse effect level (NOAEL) chosen was 100 mg/kg bw/day in a 4 weeks oral toxicity study. Systemic exposure dosage (SED) was 0.588 mg/kg bw/day for maximum use of ethylhexyl dimethyl PABA in cosmetics. Based on the risk assessment and exposure scenarios conducted in this study, the margin of safety (MOS) was calculated to be 180.18 for a sunscreen containing 8% ethylhexyl dimethyl PABA, which is the maximum level allowed by the relevant domestic authorities.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.4
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• pp.337-344
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• 2021

Background: The primary indication for using long-acting anesthetics in dentistry is extensive dental procedures that require pulpal anesthesia beyond 90 min and management of postoperative pain. Ropivacaine is an amide local anesthetic that is available at various concentrations with inherent vasoconstrictive properties at low concentrations. Ropivacaine has a 75% greater margin of safety than bupivacaine. Ropivacaine can be a good alternative to bupivacaine as a local anesthetic in dental implant surgery as it provides a longer duration of both pulpal and soft tissue anesthesia after mandibular nerve block and lowers CNS and cardiovascular toxicity. This study aimed to evaluate and compare the clinical efficacy of ropivacaine and lignocaine for implant surgery anesthesia. Methods: Fifteen patients with bilateral edentulous sites indicated for implant placement were recruited for this study. Patients aged 20-60 years of both sexes were randomly recruited. Thirty implant placements were performed in the test and control groups using ropivacaine and lignocaine with adrenaline as local anesthetics, respectively. Results: The results were analyzed statistically. The duration of anesthesia was significantly higher in the test group than in the control group. Ropivacaine was found to be superior to lignocaine in terms of the quality of anesthesia. The comparison of mean visual analog scale scores showed ropivacaine to have better anesthetic and analgesic effects than the control group. Conclusion: Ropivacaine 0.75% provides a significantly longer duration of anesthesia than lignocaine 2% with adrenaline. Ropivacaine 0.75% decreased intraoperative and postoperative analgesia compared to lignocaine 2% with adrenaline. Hence, ropivacaine 0.75% can be used as an alternative to lignocaine in implant surgeries and other intraoral surgical procedures that require a longer duration of anesthesia and analgesia.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.6
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• pp.340-346
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• 2002

The purpose of the present study was to examine the efficacy and mechanism of the PAB (para-amino benzamidine) affinity column chromatography, Viresolve NFP virus filtration, pasteurization (60$\^{C}$ heat treatment for 10 h), and lyophilization steps employed in the manufacture of urokinase from human urine as regards the removal and/or inactivation of the hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and subjected to scale-down processes mimicking the manufacture of urokinase Samples were collected at each step, immediately titrated using a 50% tissue culture infectious dose (TCID$\_$50/), and the virus reduction factors evaluated. PAB chromatography was found to be an effective step for removing HAV with a log reduction factor of 3.24. HAV infectivity was rarely detected in the urokinase fraction, while most of the HAV infectivity was recovered in the unbound and wash fractions. HAV was completely removed during the Viresolve NFP filtration with a log reduction factor of $\geq$ 4.60. Pasteurization was also found to be an effective step in inactivating HAV where the titers were reduced from an initial titer of 7.18 log$\_$10/ TCID$\_$50/ to undetectable levels within 10 h of treatment. The log reduction factor achieved during pasteurization was $\geq$ 4.76. Lyophilization revealed the lowest efficacy for inactivating HAV with a log reduction factor of 1.48. The cumulative log reduction factor was $\geq$ 14.08. Accordingly, these results indicate that the production process for urokinase exhibited a sufficient HAV reducing capacity to achieve a high margin of virus safety.