• Journal of Korean Neurosurgical Society
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• v.38 no.2
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• pp.111-115
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• 2005

Objective : Upper lumbar disc herniation is rare disease, compared with lower. The lamina of this high level lumbar vertebra is narrower than that of low level, and this have taken surgeon into important consideration for surgical methods because partial removal of lamina for discectomy weakens the base of the articular process and may result in fracture. The authors an accurate preoperative diagnosis that enables the surgeon to operative approach for preserving the facet joint. Methods : Thirteen patients with upper lumbar disc herniation have underone surgical procedure by midline approach for removal of ruptured disc fragment and paraspinal approach for removal of residual disc materials simultaneously without instrumentation. All patients who underwent surgery were analyzed and long-term follow-up was conducted. Results : At a mean follow-up of 24months, there were complete resolution of presenting radiating leg pain in 85% of the patients, 7.5% were left with minimal residual discomfort, and 7.5% derived little or no benefit from surgery. The follow-up radiologic findings of all patients shows that lamina and facet joint have preserved safely and no instability. Conclusion : Simultaneously, paraspinal with midline approach provides highly satisfactory operating methods by simplifying exposure and greatly limiting the risk of complications. This provides the basis for a planned surgical approach in which destruction of the facet joint can be avoided.

• Journal of Korean Society of Water and Wastewater
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• v.7 no.2
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• pp.24-33
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• 1993

The effects of chlorine dioxide on the oxidation of phenol and disinfection were studied in the various test water conditions. With the 0.3mg/l of chlorine dioxide dose, the spiked phenol(initial concentration: 0.1mg/l) was completely oxidized within 10 minute. The removal rate of phenol was much faster in distilled water than in ground water and filtered water. The applied dose of chlorine dioxide concentrations higher than 0.2mg/l was sufficiently enough for the complete oxidation of phenol. However, with 0.1mg/l of dose, chlorine dioxide can oxidize only 20% of the spiked phenol. The reactive substances present in test water may influence the chlorine dioxide demand in water. pH effect of oxidation rate was also investigated. Increasing the pH, the removal rate of phenol was found to be increased. The disinfection test of chlorine and chlorine dioxide were conducted and compared. The lethal effect for the both disinfectants are similarly powerful. The time for 99% inactivation of E. coli was obtained within 120 sec with the 0.2mg/l of each dose.

• Environmental Engineering Research
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• v.24 no.4
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• pp.646-653
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• 2019

Recovery of valuable metals in the industrial wastewater and sludge has attracted an attention owing to limited metallic resources in the earth. In this study, we firstly fabricated Ti/Ir-Ru electrodes by spin coating technique for effective recovery of Cu in electrowinning process. Two different Ti/Ir-Ru electrodes were fabricated using 100 and 500 mM of precursors (i.e., Ir-Ru). SEM-EDX and AFM revealed that Ir and Ru were homogenously distributed on the surface of Ti plate by the spin coating, in particular the electrode prepared by 500 mM showed distinct boundary line between Ir-Ru layer and Ti substrate. XRD, XPS, and cyclic voltammetry also revealed that characteristics of IrO₂, RuO₂, and TiO₂ and its electrocatalytic property increased as the concentration of coating precursor increased. Finally, we carried out Cu recovery experiments using two Ti/Ir-Ru as anodes in electrowinning process, showing that both anodes showed a complete removal of Cu (1 and 10 g/L) within 6 h reaction, but much higher kinetic rate constant was obtained by the anode prepared by 500 mM. The findings in this study can provide a fundamental knowledge for surface characteristics of Ti/Ir-Ru electrode prepared by spin coating method and its potential feasibility for effective electrowinning process.

• Journal of Korean Neurosurgical Society
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• v.30 no.7
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• pp.928-933
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• 2001

Intraventricular arachnoid cyst has been rarely reported. Here we present two cases of symptomatic intraventricular arachnoid cysts in the fourth ventricle and right lateral ventricle. The first patient was a 38-year-old female who complained of headache and left facial hypesthesia. Computed tomography and MR scan revealed large cystic lesion in the fourth ventricle. After cyst wall removal, facial hypesthesia disappeared immediately and headache improved slowly. The second patient was a 9-year-old girl who complained of headache, vomiting and paresthesia in her right low extremity. Cystic lesion in the right lateral ventricle was detected in the CT and MR scan. The symptoms improved after cyst wall removal. Surgical findings of these two cases showed that the cyst walls were attached firmly to the choroid plexus. Symptomatic intraventricular arachnoid cyst must be treated appropriately and we recommend complete cyst wall removal.

• Journal of Soil and Groundwater Environment
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• v.18 no.1
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• pp.78-84
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• 2013

This study was conducted in order to evaluate the removal process for long-term contamination sources including chlorinated hydrocarbons (TCE and PCE) and explosive compounds (TNT, RDX, and HMX) in underground water using a pulsed-UV system. Crystallized cells containing the contaminants were placed 10, 20, and 40 cm away from a lamp that emits pulsed-UV rays in order to examine how the removal efficiency is influenced by the distance between the source of the light and the compounds. Chlorinated hydrocarbons were completely removed in 30 minutes with a distance of 10 cm, while PCE was completely removed even with a distance of 20 cm. In the case of explosive compounds, removal efficiencies slightly varied depending on the compounds. The majority of the compounds were perfectly removed with a contact time of 10 minutes. In particular, for RDX, the results showed that complete removal was obtained within one minute, regardless of the distance from the UV source. The amount of light energy is in inverse proportion to the distance, and thus the energy reaching the compounds severely diminishes as the distance increases. Therefore, the removal efficiency decreased with increasing distance in the system.

• Clinics in Shoulder and Elbow
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• v.21 no.2
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• pp.75-81
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• 2018

Background: We investigated the resolution of pain and functional recovery of shoulder after arthroscopic removal of calcific deposits in patients with chronic calcific tendinitis. Methods: We enrolled 39 patients who were treated arthroscopically for chronic calcific tendinitis that had been non-responsive to at least 6 months of conservative treatment. We evaluated clinical outcome in terms of the American Shoulder Elbow Surgeons (ASES), the Constant score, the visual analogue score (VAS) for pain. We used plain radiography to measure the size of the calcific deposits. We also analyzed the clinical outcomes in terms of whether or not a cuff repair was performed or the degree of removal of calcific deposits. Results: We found that complete resolution of pain took on average 5.7 months after the arthroscopic treatment. The ASES and the Constant score significantly improved from the 3-month follow-up, however it took 6 months until the scores reached on average 80 points or above. We found that these clinical outcomes at the final follow-up did not significantly differ by whether or not cuff repair was performed. Similarly, we found that the clinical outcomes did not significantly differ by the degree of calcium removal. Conclusions: We found that arthroscopic removal of calcification leads to improved clinical outcomes in patients with chronic calcific tendinitis. However, our findings show it takes at least 6 months for the clinical improvement to become statistically significant. We also found that concomitant cuff repairs or the degree of removal of calcification does not affect the clinical outcome of the arthroscopic treatment.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.6
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• pp.577-585
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• 2014

A series of experiments using atmospheric-pressure non-thermal plasma coupled with transition metal catalysts were performed to remove ethylene from agricultural storage facilities. The non-thermal plasma was created by dielectric barrier discharge, which was in direct contact with the catalyst pellets. The transition metals such as Ag and $V_2O_5$ were supported on ${\gamma}-Al_2O_3$. The effect of catalyst type, specific input energy (SIE) and oxygen content on the removal of ethylene was examined to understand the behavior of the hybrid plasma-catalytic reactor system. With the other parameters kept constant, the plasma-catalytic activity for the removal of ethylene was in order of $V_2O_5/{\gamma}-Al_2O_3$ > $Ag/{\gamma}-Al_2O_3$ > ${\gamma}-Al_2O_3$ from high to low. Interestingly, the rate of plasma-catalytic ozone generation was in order of $V_2O_5/{\gamma}-Al_2O_3$ > ${\gamma}-Al_2O_3$ > $Ag/{\gamma}-Al_2O_3$, implying that the catalyst activation mechanisms by plasma are different for different catalysts. The results obtained by varying the oxygen content indicated that nitrogen-derived reactive species dominated the removal of ethylene under oxygen-lean condition, while ozone and oxygen atoms were mainly involved in the removal under oxygen-rich condition. When the plasma was coupled with $V_2O_5/{\gamma}-Al_2O_3$, nearly complete removal of ethylene was achieved at oxygen contents higher than 5% by volume (inlet ethylene: 250 ppm; gas flow rate: $1.0Lmin^{-1}$; SIE: ${\sim}355JL^{-1}$).

• Korean Journal of Bronchoesophagology
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• v.14 no.1
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• pp.23-28
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• 2008

Background and Objectives : Traditionally, the excision of submandibular gland (SMG) has been commonly used for treatment of calculi in the proximal duct or gland parenchyma. Over the last 10 years several new minimally invasive techniques including lithotripsy, sialendoscope were introduced in the treatment of sialolithiasis. But these have some limitation on large, infected calculi. The aim of this study is to assess the intraoral treatment of submadibular stones. Subjects and Method : The records of one hundred and seventy-three patients who underwent intraoral removal of submadibular sialolithiasis between June 1, 1989 and July 31, 2006 were retrospectively reviewed. Results : Stone location was distal to the edge of the mylohyoid muscle in 127 patients and proximal to gland in 48 patients (mean size of sialoliths, 7.1mm [range 3.0-25mm]). The complete removal of stones was observed in 170 (97.1%) patients regardless of size and location. Recurrence of lithiasis was found in 8 patients (then treated with intraoral removal in 5 patientsand resection of SMG (submandibular glands) in 3 patients). Acalculous sialadenitis in 9 patients (5.1%) and cyst formation in 2 patients (1.1%) was found. But no evidence of postoperative complications including hemorrhage, fistula, damage to lingual nerve were found. Conclusion : The intraoral removal of submandibular stone is useful in preservation of submandiblar function and effective in palpable stones regardless of location, size.

• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.1
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• pp.64-71
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• 2014

Mesiodens is defined as a supernumerary tooth in the premaxillary region. It can cause several clinical manifestations in normal eruption and position of adjacent teeth, such as displacement and impaction. Although the mesiodens accompanied by a clinical complication is indicated for removal, the optimal time of mesiodens removal is still controversial. Some authors suggest immediate intervention defining the removal of mesiodens as soon as possible after the first detection. On the other hand, others recommend delayed intervention which denotes the removal of mesiodens after complete root development of adjacent teeth. This case report is presented with three cases of spontaneous correction and proper alignment of rotated maxillary central incisors by extraction of mesiodens when the crowns of rotated incisors were completely formed while the roots of them were at an early developmental stage.

• KSBB Journal
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• v.19 no.3
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• pp.236-240
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• 2004

Korean wastewaters have higher nitrogen concentrations than typical wastewaters of other countries. Most treatment processes such as activated sludge processes will need to supplement extra carbon sources for a complete removal of remaining nitrogen after the initial wastewater treatment, Because of these difficult matters, we have searched wastewater treatment methods that require no additional carbon sources. Wastewater treatment by microalgae in photobioreactors, using a green eukaryotic microalgae, Chlorella kessleri, showed a promising results and thus was selected to study further. This system is not intended to replace the conventional system but is to assist the existing biological treatment systems as a supplemental nitrogen removal process. Thus the secondary treated livestock wastewater was tested. Column type photobioreactors developed in our laboratory were used. When aerated with 5% CO$_2$ balanced with air at 1 vvm and illuminated at 100 ${\mu}$mol/㎡/s under 25$^{\circ}C$ and PH 7-8 by CO$_2$ buffering effect, the maximum nitrogen removal rate was 2.6 mg/L/hr. The results confirmed a possibility of microalgal wastewater treatment system as a secondary system to remove extra nitrogen sources. Based on these experimental results, the size of the optimal microalgal wastewater system was calculated. For the wastewater whose initial nitrogen concentration of 150 mg/L, the optimal batch system was found to be a 2 stage system with a combined retention time of 4.6 day. From the continuous experiments, nitrogen removal rates were examined under different dilution rates and 2 stage system was also found to be the optimal system. The combined retention time for the continuous system was 3.5 days. It is expected that conventional biological wastewater treatment systems followed by microalgal systems would reliably decrease the nitrogen concentration below the government criteria even for the livestock wastewater with low C/N ratio.