• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2677-2682
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• 2011

Direct nitrolysis of 3,7-dinitro-1,3,5,7-tetraazabicyclo[3,3,1]nonane (DPT) is a feasible way to synthesize HMX, and it has multiple practical applications. In this paper, a new nitrolysis process involving the use of an $N_2O_5-HNO_3$ system catalyzed by acidic ionic liquids (AILs) was developed. The results show that [$Et_3NH$]TsO was the best catalyst among the 28 AILs used and that HMX was formed at a higher yield of 61%, compared to 45% without any AIL. Moreover, with the addition of $N_2O_5$, the yield was further increased to a maximum value of 69%. The AILs were also efficiently recovered by simple extractions without any apparent loss of catalytic activity, even after five runs.

• Journal of Dental Anesthesia and Pain Medicine
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• 제20권1호
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• pp.39-44
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• 2020

Homozygous familial hypercholesterolemia (HoFH) is a rare inherited disorder that presents as abnormally elevated levels of low-density lipoprotein cholesterol and premature heart disease, requiring frequent intervention through lipid apheresis for management. The risk of perioperative cardiac events is higher in patients with HoFH because of its pathophysiological manifestations in the vascular system. Careful cardiac precautions and anesthetic assessments are necessary to ensure patient safety. In the following case report, we discuss the clinical course and anesthetic considerations for a 14-year-old girl with HoFH undergoing sedation for dental extractions and mandibular molar uprighting in an outpatient oral surgery clinic. Considerations included the use of heparin in the patient's weekly plasma lipid apheresis treatment. In order to reduce the risks of peri- and postoperative bleeding and perioperative cardiac events, the operation was scheduled for 4 days after apheresis. This allowed for adequate heparin clearance, while also reducing the likelihood of possible cardiac events. A literature review revealed no results for the outpatient management of patients with HoFH undergoing sedation for noncardiac procedures. Our reported case serves as a clinical example for physicians to be utilized in the future.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제23권3호
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• pp.238-243
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• 2001

Purpose : The purpose of this study was to determine radiologic variables affecting extraction of impacted mandibular third molar. Materials and Methods : This study was investigated on 44 consecutive extractions of unilateral impacted mandibular third molars (Male;34, Female;10, Mean age;24.98, Age range;19-35). Fourteen radiologic variables, which were actual value except only one, were evaluated to establish their relation to the operation time. The Pearson correlation coefficient and Stepwise procedures for regression analysis were carried out. Results : Eight variables (depth, angulation, ramus width, relationship to the second molar, distal ramus depth, mesial ramus depth, mesial periodontal ligament width and follicle) showed a statistically significant relation to the operation time(Pearson correlation coefficient, p<0.05). Two variables, depth and mesial periodontal ligament width, showed the most powerful and just relation to the operation time($r^2$ = 0.349, p<0.05). Conclusion : This study shows that our results can help general practioner to estimate the operation time of extraction of impacted mandibular third molars by measuring two radiologic variables ; depth and mesial periondontal ligament width.

• 대한치과교정학회지
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• 제48권1호
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• pp.57-62
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• 2018

Piezoelectric surgery is a novel surgical approach used in orthodontic treatment for rapid tooth movement. This paper presents a case series wherein osseous outgrowths were observed in response to piezosurgery-assisted en-masse retraction. Sixteen patients requiring upper premolar extractions were treated with miniscrew-supported en-masse retraction and received minimally invasive decortication via piezosurgery. Computed tomography (CT) of the maxillary anterior region was performed to investigate the nature of the outgrowths. In 8 of the 16 patients, hemispheric or disc-shaped osseous outgrowths were observed on the sites where piezosurgery was performed during retraction. CT images revealed that these outgrowths were alveolar bone. This case series presents a previously unreported osseous response to piezosurgery-assisted tooth movement during orthodontic treatment. The response is mostly transient and is observed in 50% of the treated patients, suggesting a bone turnover that can be assessed clinically and radiographically.

• Imaging Science in Dentistry
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• 제44권2호
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• pp.155-160
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• 2014

Purpose: The purposes of this study were to develop a workstation computer that allowed intraoperative touchless control of diagnostic and surgical images by a surgeon, and to report the preliminary experience with the use of the system in a series of cases in which dental surgery was performed. Materials and Methods: A custom workstation with a new motion sensing input device (Leap Motion) was set up in order to use a natural user interface (NUI) to manipulate the imaging software by hand gestures. The system allowed intraoperative touchless control of the surgical images. Results: For the first time in the literature, an NUI system was used for a pilot study during 11 dental surgery procedures including tooth extractions, dental implant placements, and guided bone regeneration. No complications were reported. The system performed very well and was very useful. Conclusion: The proposed system fulfilled the objective of providing touchless access and control of the system of images and a three-dimensional surgical plan, thus allowing the maintenance of sterile conditions. The interaction between surgical staff, under sterile conditions, and computer equipment has been a key issue. The solution with an NUI with touchless control of the images seems to be closer to an ideal. The cost of the sensor system is quite low; this could facilitate its incorporation into the practice of routine dental surgery. This technology has enormous potential in dental surgery and other healthcare specialties.

• Preventive Nutrition and Food Science
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• 제16권1호
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• pp.37-44
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• 2011

The potential probiotic of a total of 15 Bacillus species isolated from Korean soybean paste (doenjang) was evaluated. Among those tested, the CSY191 and CSY388 strains were selected as probiotic bacteria due to their acid and bile tolerance, respectively. These strains were classified as Bacillus subtilis based on morphological, physiological, and chemotaxonomic features as well as on phylogenetic analysis based on their 16S rDNA sequences. These strains CSY191 and CSY388 showed a significant survival with rate range of 30.0 to 58.3% and of 31.0% to 58.1%, respectively, under artificial gastric acidic conditions at pH 3.0. These CSY191 and CSY388 strains appeared to have high antimicrobial activity against Salmonella Typhimurium, Bacillus cereus and Listeria monocytogenes. Also, methanol extractions (surfactin-like compounds) of strain CSY191 and strain CSY388 activated RAW264.7 microphages and induced the production of nitric oxide (NO) in a concentration-dependent manner, respectively. Therefore, strain CSY191 and strain CSY388 can be used as potential probiotics.

• Biomolecules & Therapeutics
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• 제8권1호
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• pp.63-72
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• 2000

We intended to show some basic requirements for spectrum analysis of electroencephalogram (EEG) by visualizing the differences of the results according to different values of some parameters for analysis. Spectrum analysis is the most popular technique applied for the quantitative analysis of the electroen- cephalographic signals. Each step from signal acquisition through spectrum analysis to presentation of parameters was examined with providing some different values of parameters. The steps are:(1) signal acquisition; (2) spectrum analysis; (3) parameter extractions; and (4) presentation of results. In the step of signal acquisition, filtering and amplification of signal should be considered and sampling rate for analog-to-digital conversion is two-time faster than highest frequency component of signal. For the spectrum analysis, the length of signal or epoch size transformed to a function on frequency domain by courier transform is important. Win dowing method applied for the pre-processing before the analysis should be considered for reducing leakage problem. In the step of parameter extraction, data reduction has to be considered so that statistical comparison can be used in appropriate number of parameters. Generally, the log of power of all bands is derived from the spectrum. For good visualization and quantitative evaluation of time course of the parameters are presented in chronospectrogram.

• Journal of the korean society of oceanography
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• 제37권2호
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• pp.58-65
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• 2002

The study of microbial communities in sediments is impaired by the lack of reliable extraction methods. This study reports on the efficiency of recovery of a method for extracting bacteria, protists and diatoms from sandy sediments using a modified decant/fix method. The best extractions were achieved after fixation with a microtubule stabilising fixative and subsequent sonication for 80 seconds. We estimate that the efficiencies of recovery of bacteria and mixed heterotrophic flagellates were $96.4{\pm}3.5\%$ and $96.9{\pm}4.6\%$, respectively. Diatoms were recovered with an efficiency of 38-83% and varied considerably from species to species. This study suggests that the decant/fix method is effective in extracting small cells such as bacteria and heterotrophic flagellates, and that the efficiency of recovery of the method varies due to cell length and different types of organisms. When microbial carbon biomass had been underestimated by up to 32%, with much of that relating to larger cells such as microalgae and ciliates. We note that the corrected abundances may be still a subset of the total numbers present.

• 자원환경지질
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• 제30권2호
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• pp.105-116
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• 1997

This study is for extent of polluted area by acid mine drainage from the Daeseong coal mine, Keumsan. Black shales of the Changri Formation containing the Daeseong coal mine are geochemically similar to those from the North America as well as Europe. Comparing with geochemical compositions and relative ratios, coal bearing and non-coal bearing soils are similar to the stream sediments influenced and not influnced by the acid mine drainage, respectively. These characteristics suggest that acidification of the soils and of the stream sediments are related to the the coal bearing black shale. Soil waters beneath the coal bearing soil have low pH and high cation contents than those beneath non-coal bearing soil, suggestive of extractions of cations with increasing oxidizations within the soils. Surface waters show that those influenced by the acid mine drainage are low pH, and have high $SO_4{^{2-}}$, $Mg^{2+}$, $Fe^{2+}$, Mn and slightly lower DO, suggesting that heavy pollutions have been progressed in these area. Geochemical comparisons between the polluted surface water and adjacent black shales suggest that pollutions of the surface water are related to the black shales.

• Toxicological Research
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• 제13권3호
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• pp.193-196
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• 1997

Matricaria Chammomillal L., Foemiculum Vulgare mill, and Plantago Psylium L. have been screened for their hepato protective activities against liver damge induced by $CCl_4$ intoxication in mice. Hydroalcoholic extractions (2:8) of herbal drugs were concentrated in vacuo and concentrated crude extracts of Matrica Chammomilla L. and Foeniculum Vulgare mill were orally administered at doses of 100 mg/kg, 200 mg/kg, 400 mg/kg, and 800 mg/kg. Plantago Psyllium was given at doses of 50 mg/kg, 100 mg/kg, 200 mg/kg, and 400 mg/kg. Liver protective activities of these herbs were determined after administration of $CCl_4$ Liver size, serum enzyme activities, sleeping time, and histopatology of the liver were examined one hour after administration of $CCl_4$. ALT and AST activities, liver weight and sleeping time decreased in groups that received 400 mg/kg of Matricaria Chammomilla L. or Foeniculum Vulgare. Histological investigation showed significant increase in hepatic cell regeneration and reduction in liver injury. The group that received 100 mg/kg Plantago Psylium showed liver protection but protection was not significant in other doses.