• Journal of Korean Society of Environmental Engineers
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• v.33 no.4
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• pp.275-280
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• 2011

In the present work, the aerobic particle's characteristics were enhanced. A polymer was used to make aerobic granular sludge in short period of time. And operation parameters were calculated for organic matter removal in domestic wastewater using a sequencing batch reactor (SBR). The experiment for sewage (Influent concentration of 63~72 mg COD/L) by using mature aerobic granular sludge showed the organic matter removal rate k and oxygen utilization coefficient a', b' were $10.161d^{-1}$ and 0.87 mg $O_2/mg$ $COD_r$, 0.11 mg $O_2/mg$ MLVSS d respectively. Therefore, it was more effective than K value $5{\sim}8d^{-1}$ of conventional activated sludge process. The sludge synthetic value and sludge auto-oxydation value were 0.45 mg VSS/mg $COD_r$ and 0.05 mg VSS/mg MLVSS d respectively. Consequently, mortality rates of microorganisms was lower than conventional activated sludge process.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.235-238
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• 1995

모든 살아있는 조직은 표면전위(surface electropotentials)를 가지고 있으며, 이는 조직에 손상를 가져오는 상처가 발생되었을 때 그 상처를 치료하는데 큰 역할을 담당하고 있다. 즉, 상처부위에 인위적으로 표면전위의 특성을 가진 전기적인 자극을 가함으로서 상처의 치료효과를 높일 수 있으며, 그 중에서도 상처의 발생 직후에 음(-)의 전기자극을 가할 때 높은 치료효과를 나타내는 것으로 알려져 있다. 본 연구는 상처의 치료에 전기자극을 사용할 때, 자극의 특성 변화가 치료의 효과를 높일 수 있는가에 대한 기초 연구로서 수행하였다. 즉, 쥐의 복부부위를 일정한 크기로 절개하고, 그 부위에 1mA와 10mA의 자극 펄스를 지속시간을 10msec와 100msec로 변화하면서 $1\sim3$일간 제시한 후 상처가 치료된 정도를 비교하였다. 모든 자극이 끝난 후 상처부위에 대한 조직검사를 수행하여 육아조직(granulation tissue)의 상태를 관찰하였다. 그 결과 전기자극을 전혀 가하지 않은 그룹에 비하여 전기자극을 행한 그룹들의 육아조직에 있어서 그 형성 상태가 양호하였고, 괴사현상이 나타나지 않았으며, 염증의 정도가 낮게 나타났음을 발견하였다. 또한, 자극의 횟수를 증가할수록 전기자극으로 인한 치료의 효과가 크게 나타났음을 알 수 있었다. 그러나, 각 그룹 내에서 자극의 특성을 변화시키며 수행한 검사의 결과는 큰 차이를 보이지 않았다.

• Korean Journal of Bronchoesophagology
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• v.9 no.1
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• pp.67-74
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• 2003

Larygopharyngeal reflux(LPR) is one form of the Gastroesophageal Reflux Diseases(GERD). It is known to cause various kinds of otolaryngologic symptoms such as hoarseness, globus sensation in throat, chronic throat clearing, and chronic cough, Disease entities diagnosed by otolaryngologists as posterior laryngitis, globus pharyngeus and reflux laryngitis should be suspected as LPR-related diseases. The nizatidine(AXID), as a Histamine H2-receptor antagonist, reduces gastric acid secretion and improves gastric motility function. Objectives : The effect of nizatidine using 150mg b.i.d was evaluated for symptom relief and improvement of laryngoscopic findings in patients with LPR. Materials and Methods : In 30 multicenter, observational trial performed nationalwidely in Korea. 308 patients with LPR symptom were observed to evaluate their symptoms and larygnoscopic findings after 4weeks, 8weeks, 12weeks of treatment with nizatidine. Results : The symptoms of LPR including globus sensation, chronic throat clearing and hoarseness, are reduced significantly after 4 weeks, 8weeks, and 12weeks of treatment(p<0.05). The laryngoscopic findings including diffuse erythema, edema and granulation are improved after nizatidine treatment(p<0.05). and the efficacy of nizatidine on LPR-related sympoms after 4 weeks is 88.6%, and those of after 8 weeks and 12weeks were 92.6%, and 99.1% in ITT(Intent To Treatment) group(p<0.05). And PPA(Per Protocol Analysis)group showed 93.7%, 97.3%, and 99.1% of efficacy after 4, 8, and 12 weeks of nizatidine treatment(p<0.05). Conclusion : These results indicate that in patient with LPR, nizatidine 150mg b.i.d treatment very effectively reduces LPR symptoms and improves laryngoscopic findings as well as reduces gastric acid secretion and improves gastric motility function.

• Korean Journal of Bronchoesophagology
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• v.5 no.2
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• pp.153-158
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• 1999

Background and Objectives : The treatment of supraglottic stenosis remains a challenging problem in the field of otolaryngology due to its association with dyspnea, dysphagia, and frequent recurrence. Any satisfactory treatment is not yet known. The author experienced six cases of supraglottic stenosis and report the successful treatment of five cases by repeated endoscopic laryngeal excision with KTP-532 laser under suspension layngoscopy. Materials and Methods : Six adults who were treated for supraglottic stenosis between March 1994 and December 1998 at the Department of Otoloaryngology-Head and Neck Surgery, Korea University Medical Center were studied retrospectively. The patients were placed under general anesthesia followed by endoscopic laryngeal excision with KTP-532 laser under supension laryngoscopy. The scar tissue and granulation tissue were visualized with an operating microscope, and then removed using KTP-532 laser (15watts, continuous mode). Intraoperative local steroid(Triamcinolone ) was injected in all cases after the stenotic portions were removed. Results : Endoscopic excision was performed in five cases ; among the five cases, cricoid cartilage was concomitantly removed in two cases, and epiglottis was removed in one case. Satisfactory swallowing and airway respiration were possible in all five patients who underwent endoscopic widening. Conclusion : The treatment of supraglottic stenosis is different from that of tracheal or glottic stenosis in that supraglottic stenosis is mainly developed in membraneous form. Repeated laser excision and local steroid injection under suspension laryngoscopy is an effective and recommend able method for the treatment of supraglottic stenosis.

• Korean Journal of Bronchoesophagology
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• v.16 no.1
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• pp.33-38
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• 2010

Titania nanomaterials are widely used as cosmetics and dyes, however the impacts on human health are uncertain, We investigated the biodistribution of inhaled titania nanoparticles in rats, Methods Eight weeks-old SD rats were intubated and inhaled with 3 mg titania nanoparticles, twice a week, for 2 weeks, After inhalation, the rats were sacrificed and tissues or heart, lung. intestine, brain, and liver were obtained, We investigated the tissues with optical microscope (OM), transmission electron microscope (EM), scanning EM, And to analyze titania concentration of each tissue, we lysed the tissues with radioimmunoprecipitation assay (RlPA) lysis buffer or acid. Results Granulation tissues in lung were confirmed on the optical microscope, however the other organs had no abnormalities in OM images, In EM images, the rats which inhaled titania nanoparticles showed calcium deposition at heart, brain, and intestine, Titania concentration in lung was increased on the inhaled rat sacrificed I month after last exposure. Conclusion Inhaled titania nanoparticles is thought to be deposited and make inflammatory reaction in lung, and the deposition was not efficiently cleared over a month. However inhaled titania nanoparticles may rarely pass through the alveolus-blood barrier and distribute to other organs of the bod.

• Journal of Chest Surgery
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• v.10 no.1
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• pp.7-17
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• 1977

The increasing frequency of post-tracheostomy stenosis parallels the increase in the incidence of tracheostomy. The development of stenosis of trachea following the operation of tracheal tumor or tracheostomy is a very serious complication. The continuing need for an adequate tracheal substitute has not been answered, despite the necessities of excision and reconstruction of the trachea to keep for effective ventilation. Experimental tracheal reconstuction, with a prosthesis of heavy Marlex mesh and pericardium, _ vas performed in twelve dogs. Five to six tracheal ring circumferential defects were created and were bridged with heavy Marlex mesh fashioned into a tube of suitable diameter. Group A: A prepared cylinder of Marlex mesh was anastomosed outside the cut ends of the trachea. Group B: The external surface of the prepared cylinder of Marlex mesh was completely covered with suitably sized patch of pericardium and overlapped all margin of the Marlex mesh by 2 to 3 mm in each direction. Group C: The internal surface of the prepared cylinder of Marlex mesh was covered with suitably sized patch of pericardium and overlapped all margin of the Marlex mesh by 2 to 3 mm in each direction. The results of this exepriment were as follow: 1. In group A and B, the graft was well bridged with new granulation and fibrous tissue, and the lumen of trachea kept good patency for effective ventilation.. The interstices of Marlex became uniformly infiltrated with young well vasculated connective tissue. Epithelization has not yet occurred at 4 weeks in each group, but there were evidences of new growing mucosa at grafted site in 6 weeks. The remainder of the prosthesis was completely covered with glistening epithelium and the underlying fibrous tissue became more matured with little inflammation. These findings were more striking in group B than group A. 2. In group C, the covered pericardium was necrotized with stenosis of the lumen of grafted site due to poor blood supply.

• Journal of Oral Medicine and Pain
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• v.22 no.2
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• pp.309-325
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• 1997

In order to set the lasing variables and evaluate, clinically, the therapeutic effects of a pulsed Nd:YAG laser on oral lesion, the author applied the laser energy from a fiberoptic delivered, free running, pulsed Nd:YAG laser (wavelength 1064nm, Pulse duration 120$\mu$sec, fiber diameter 200$\mu$m/320$\mu$m) to 22 cases of oral soft tissue lesions and 6 cases of oral hard tissue lesions. The obtained results were as follows : 1. The effective excision with contact mode and the effective hemostasis of accompanied bleeding with noncontact mode were occurred by lasing on oral soft tissue lesions with fiber diameter of 320$\mu$m under the variables of 2.0~4.0W and 20~50Hz which were controlled into high power/low pulses for excision, low power/high pulses for hemostasis, low power in granulation tissue and high power in fibrous tissue according to therapeutic goals and tissue conditions. 2. About 50% of decreasing effect on hypersensitivity was occurred by lasing with non-contact and contact mode on cervical abrasion which caused dentinal hypersensitivity with fiber diameter of 320$\mu$m under the variables of 0.7 - 1.0W and 10Hz which were applied 2~3 times with 1 week interval. 3. The effective sterilization of infected root canal and lesion of periapical abscess was occurred by lasing with contact and spiral modes on wall of root canal and periapical abscess with fiber diameter of 200$\mu$m of which the tip was placed about 1mm shorter than root canal length under the variables of 1.OW and 10Hz.

• KSBB Journal
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• v.25 no.2
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• pp.137-141
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• 2010

Citric acid is a natural preservative and is used to add a sour taste to foods and soft drinks. For the preparation of stable food additives of citric acid, a coating process using vegetable oil was developed. Coating materials used were purified soy bean oil and carnauba wax. The yield of coated citric acid was up to 95% in both cases. The contents of coating materials was 20~33% in the total composition and the coating efficiency was 95.2 ${\pm}$ 0.01%. The surface of coated citric acid was much smoother and more homogeneous than that of original citric acid according to SEM data. The coated citric acid can be used to as a stable food additive and also would be applied to nutraceuticals and cosmetic ingredients.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.4
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• pp.342-349
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• 2009

This study investigated the growth characteristics of carbon nanotubes (CNTs) by changing a period of annealing time and a $C_{2}H_{2}/H_2$ flow ratio at temperature as low as $450^{\circ}C$ with inductively coupled plasma chemical vapor deposition. The 1-nm-thick Fe-Ni-Co alloy thin film served as a catalyst layer for the growth of CNTs, which was thermally evaporated on the 15-nm-thick Al underlayer deposited on the 50-nm-thick Ti diffusion barrier. The annealing at low temperature of $450^{\circ}C$ brought about almost no granulation of the catalyst layer, and the CNT growth was not affected by a period of annealing time. A study of changing the flow rate of $C_{2}H_{2}$ and $H_2$ showed that as the ratio of the $C_{2}H_{2}$ flow rate to the $H_2$ flow rate was lowered, the CNTs were grown to be longer With further decreasing the flow ratio, the length of CNTs reached the maximum and then became shorter. Under the optimized gas flow rates, we successfully synthesized CNTs with a uniform length over a 4-inch Si wafer at $450^{\circ}C$.

• Advances in Traditional Medicine
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• v.7 no.1
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• pp.51-64
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• 2007

Mucus is an aqueous gel complex with a constitution of about 95% water, high molecular weight glycoprotein (mucin), lipid, salts etc. Mucus appears to represent a significant barrier to the absorption of some compounds. Natural mucoadhesive agent was isolated and purified from the aqueous extract of the seeds of prosopis pallida (PP). Formulated tablet with the isolated material by wet granulation method. Some natural edible substances are in consideration for candidates as mucoadhesive agents to claim more effective controlled drug delivery as an alternative to the currently used synthetic mucoadhesive polymers. Subjected the materials obtained from natural source i.e. PP and standard synthetic substance, sodium carboxymethyl cellulose for evaluation of mucoadhesive property by various in vitro and in vivo methods. Through standard dissolution test and a model developed with rabbit, evaluated in vitro controlled release and bioadhesive property of theophylline formulation. Mucoadhesive agent obtained from PP showed good mucoadhesive potential in the demonstrated in vitro and in viνo models. The results suggest that the mucoadhesive agent showed controlled release properties by their application, substantially. In order to assess the gastrointestinal transit time in vivo, a radio opaque X-ray study performed in healthy rabbit testing the same controlled release formulation with and without bioadhesive polymer. Plasma levels of theophylline determined by the HPLC method and those allowed correlations to the in vitro mucoadhesive study results. Better correlation found between the results in different models. PP may acts as a better natural mucoadhesive agent in the extended drug delivery system.