• 대한기계학회논문집B
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• 제23권9호
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• pp.1151-1162
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• 1999

The effects of radial heat and $H_2O$ diffusion on the evolution of silica particles in coflow diffusion flames have been studied experimentally. The evolution of silica aggregate particles in coflow diffusion flames has been measured experimentally using light scattering and thermophoretic sampling techniques. The measurements of scattering cross section from $90^{\circ}$ light scattering have been utilized to calculate the aggregate number density and volume fraction using with combination of measuring the particle size and morphology through the localized sampling and a TEM image analysis. Aggregate or particle number densities and volume fractions were calculated using Rayleigh-Debye-Gans and Mie theory for fractal aggregates and spherical particles, respectively. Flame temperatures and volumetric differential scattering cross sections have been measured for different flame conditions such as inert gas species, $H_2$ flow rates, and burner injection configurations to examine the relation between the formation of particles and radial $H_2O$ diffusion. The comparisons of oxidation and flame hydrolysis have also been made for various $H_2$ flow rates using $N_2$ or $O_2$ as a carrier gas. Results indicate that the role of oxidation becomes dominant as both carrier gas($O_2$) and $H_2$ flow rates increases since the radial heat diffusion precedes $H_2O$ diffusion in coflow flames used in this study. The effect of carrier gas flow rates on the evolution of silica particles have also been studied. When using $N_2$ as a carrier gas, the particle volume fraction has a maximum at a certain carrier gas flow rate and as the flow rate is further increased, the hydrolysis reaction Is delayed and the spherical particles finally evolves into fractal aggregates due to decreased flame temperature and residence time.

• 대한지하수환경학회지
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• 제6권4호
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• pp.159-170
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• 1999

초정지역에서 산출되는 탄산수에 대한 수리화학적 연구를 수행하였다. 초정탄산수는 낮은 pH(5.0~5.8). 높은 이산화탄소함량($Pco_2$＜$10^{0.31}$atm). 높은 TDS 함량을 갖는 것으로 특징되며. 화학적으로 Ca-$HCO_3$형에 속한다. 탄산수의 화학적특성은 지하수가 심부로 순환하는 과정에서 심부기원의 이산화탄소와의 반응을 통하여 탄산수가 형성되었음을 지시하며. 낮은 pH를 갖는 탄산수는 물-암석(화강암) 반응이 활발히 진행되면서 지화학적으로 진화된 것으로 판단된다. 또한 높은 $NO_3$함량은 탄산수가 천부로 상승되는 과정에서 주변지하수와 혼합된 특성을 지시한다. 초정 탄산수의 진화과정은 이산화탄소의 공급. 물-암석반응 및 혼합작용으로 설명할 수 있다. 이러한 진화과정을 열역화적으로 확인하고자 지화학 반응을 PHREEQC를 이용하여 모델링하였다. 비록 모델링은 사장석자의 반응에 국한되었지만. 탄산수의 진화과정에서 pH 및 Ca와 Na함량 변화양상에 대한 타당한 설명을 제시하고 있다.

• Journal of Chest Surgery
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• 제42권2호
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• pp.272-274
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• 2009

칼돌기 부위에 고통을 느끼는 칼돌기 통증은 흔하지 않은 근골격계 질환으로 전흉부와 상복부, 목, 양측 어깨, 등으로 통증이 방사될 수 있다. 진단에서 중요한 것은 이러한 통증이 칼돌기의 이상에 의해서 발생할 수 있다는 것을 임상적으로 알고 있어야 한다는 것이다. 2 증례의 칼돌기 통증 환자를 경험하였는데, 칼돌기 부위를 가볍게 누르면 전흉부와 상복부의 통증이 반복적으로 재생산될 때 진단하였다. 수년간 칼돌기 통증으로 고통 받아 왔던 첫번째 증례 환자에서는 칼돌기 제거수술을 하였고, 두번째 증례 환자에서는 국소마취제를 주사하여 치료하였다.

• 정신신체의학
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• 제7권1호
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• pp.10-25
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• 1999

2세이상의 어린이는 성적 흥분을 느낄 수 있기에 만지거나 자위행위 등의 성적인 즐거움을 찾기 시작 한다. 60년대 후반부터 70년대 초반사이 산부인과 의사 Masters와 사회사업가 Johnson은 인간의 성반응 단계를 흥분기, 고원기, 오르가슴기, 반응소실기의 4단계로 나눠 설명하였고, 여성에게는 무반응기가 없어 여러번의 오르가슴이 가능함을 밝혔다. 그들의 성치료원칙은 행동치료에 입각하여 감각초점법과 부부치료, 성교육등으로 구성되어있다. Masters와 Johnson이후 정신과 의사이자 정신분석가인 Kaplan이 1970년대 초반에 정신분석적 정신치료와 행동치료를 결합한 '새로운 성치료'를 제안했다. 그리고, 성기능 장애를 3가지 카테고리로 재분류했다. 1980년대 이후는 남성의 발기부전의 치료를 중심으로 의학적 치료방법론이 대세를 이루고 있는데, 음경 보속물, 국소주사치료, 경구약제등이 발달하였다. 최근 Sildenafil(Viagra)이 등장해 남성 발기부전 치료의 최선의 선택으로 받아들여지고 있다.

• The Korean Journal of Pain
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• 제19권1호
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• pp.17-21
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• 2006

Background: Cyclic guanosine monophosphate (cGMP) plays an important role in the modulation of nociception. Although local sildenafil produces antinociception, by increasing cGMP through the inhibition of phosphodiesterase 5, the effect of spinal sildenafil has not been determined. The authors evaluated the effects of intrathecal sildenafil on the nociceptive behavior evoked by formalin injection and thermal stimulation. Methods: Lumbar intrathecal catheters were implanted into rats, with formalin and Hot-Box tests used as nociceptive models. The formalin-induced nociceptive behavior (flinching response) and withdrawal latency to radiant heat were measured, and the general behaviors also observed. Results: The intrathecal administration of sildenafil produced dose-dependent suppression of the flinches in both phases in the formalin test, and increased the withdrawal latency in the Hot-Box test. No abnormal behaviors were noted. Conclusions: Sildenafil, an inhibitor of phosphodiesterase 5, is active against the nociceptive state evoked in the spinal cord by formalin and thermal stimulations. Accordingly, spinal sildenafil may be useful in the management of pain.

• The Korean Journal of Pain
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• 제19권1호
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• pp.87-90
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• 2006

Background: There are many ways to provide superior analgesia for postoperative pain after abdominal surgery of which epidural analgesics with opioids and local analgesics are the most useful. In an effort to maximize the level of analgesia and to minimize the side effects, ketamine, midazolam, clonidine, and adrenalin can be co-administrated as an adjuvant. This study examined the analgesic effect and side effects of midazolam compared with those given an epidural injection of bupivacaine, fentanyl and ketamine. Methods: In a double blind randomized controlled trial, 50 patients received either fentanyl $0.3{\mu}g/kg/h$ and ketamine 0.1 mg/kg/h (Group FK) or fentanyl $0.3{\mu}g/kg/h$, ketamine 0.1 mg/kg/h and midazolam 0.4 mg/h (Group FKM), added to 0.125% of bupivacaine at a rate of as much as 2 ml/h, for patient controlled epidural analgesia (PCEA) after low abdominal surgery. Ten minutes before surgery, the patients received either 10 ml of 0.125% bupivacaine with 0.5 mg/kg of ketamine or 10 ml of 0.125% bupivacaine with the same amount of normal saline, added to fentanyl $50{\mu}g$. The pain score and the side effects were recorded at 1, 3, 6, and 24 hours after surgery. Results: There was no difference in the pain score except for the VAS on coughing 1 hour after surgery. FKM group had fewer side effects. Conclusions: There was a better analgesic effect and fewer side effects with the addition of epidural midazolam to bupivacaine and fentanyl with ketamine formula. However, more study on the dose and route of administration will be needed.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
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• pp.85-94
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• 2002

Computational flow dynamics(CFD) has been frequently applied to the waste incinerators to understand the flow performance for various design and operating parameters. Though it needs many simplifications and complicated flow models, the reasonability of its results is not fully evaluated. For example, the inlet condition is calculated from an arbitrarily assumed properties of combustion gas release from the waste bed, since the combustion in the bed is difficult to be predicted. In this study, the computational modeling and calculation procedures of CFD for the grate type waste incinerator were evaluated using comparative simulations. Though the assumption method on the generation of the combustion gas directly affected the temperature and gas species concentrations, the overall flow pattern was dominated by the secondary air jets. The gaseous reaction could be included by assuming the release of the products of incomplete combusion from the bed. However, the reaction effficiency cannot not be directly evaluated from the species concentration, since it is not possible to simulate the actual co-existence of fuel rich or oxygen rich puffs over the bed. In predicting the turbulence, the higher order model, such as Reynolds stress model, gave difference shape of local recirculation zones, but similar results was acquired from the standard $k-{\varepsilon}$ model. Introducing radiation model was required for accurate temperature prediction, but it also caused heat imbalance due to the fixed temperature of the inlet, i.e. the waste bed. Thus, the computational modeling procedures on incinerators and the analysis of the predicted results should be progressed carefully. Though not validated experimentally, current simulation method is capable of comparative evaluation on the flow-related parameters such as the furnace shape and secondary air injection using identical inlet conditions. Quantitative analysis using measures of the residence time and mixing is essential to compare the flow performance efficiently.

• The Korean Journal of Pain
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• 제14권2호
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• pp.218-224
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• 2001

Background: Response to diagnostic blocks does not consistently predict the outcome of interventional facet denervation. We investigated the relationship between pain relief by the percutaneous radiofrequency denervation of the lumbar zygapophysial joints with the result of facet joint diagnostic local anesthetic injection in patients with back pain originating from the lumbar zygapophysial joint. Methods: There were 35 patients enrolled, with ranging in age from 25 to 76 years ($52.6{\pm}12.7$ years, mean ${\pm}$ SD). We studied 7 men (20%) and 28 women (80%). All patients underwent double diagnostic block of $L_{3/4}$, $L_{4/5}$ and $L_5-S_1$ facet joint with 0.5% bupivacaine. The 35 patients fell into the following group. (1) Group A (n = 16): those who felt clear relief (pain free with Likert scale) from the double diagnostic block (2) Group B (n = 19): 11 patients who were always equivocal in their response to the double diagnostic block and 8 patients who were either pain free or equivocal in their response to the double diagnostic block. All 11 patients were done the facet joint denervation. The effect on the pain was evaluated with 4 point Likert scale 1, 6 and 12 weeks after the procedure. We evaluated the relationship between the pain response to diagnostic block and the pain relief with facet joint denervation. Results: Significant correlation was observed between the response to diagnostic block and pain relief with facet denervation (P < 0.05). We found no correlation between the categories of spinal operation and pain response to facet denervation (P value > 0.05). Conclusions: A satisfactory result of lumbar facet joint denervation can be obtained in many patients, especillay in patients whose pain were relieved by the diagnostic double facet joint block. It may be said that facet joint denervation for mechanical low back pain using radiofrequency thermocoagulation is a safe, easy, and repeatable technique.

• Journal of Pharmaceutical Investigation
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• 제36권6호
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• pp.355-361
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• 2006

Intraarticular corticosteroid injections for therapy of rheumatic arthritis are administered with the aim of optimal local anti-inflammatory effect at the injection site. Since the side effects of corticosteroidal drug, dexamethasone(DEX), administered at hish dose limited the therapeutic efficacy, there was a need to design a new drug delivery system for controlled release of dexamethasone. As a prodrug for continuous therapeutic efficacy, dexamethasone-21-palmitate(DEX-PAL) was prepared via esterification of palmitoyl chloride and dexamethasone. DEX-PAL was identified by NMR and MASS analysis. DEX-PAL or DEX was entrapped in lipid nanosphere which could be prepared by using a self emulsification-solvent evaporation method. Physicochemical characteristics such as mean particle diameter, zeta potential and drug loading efficiency of the lipid nanospheres were investigated with variation of either the kind of lipid or the lipid composition. The lipid nanospheres had a mean diameter $83{\sim}95$ nm and DEX-PAL loading efficiency of up to 95%. The drug loading efficiency increased with the increase of aliphatic chain length attached to the phospholipid. The incorporation of cationic lipid was very efficient for both reducing particle size of lipid nanospheres and enhancing drug loading efficiency. The lipid nanospheres containing DEX-PAL may be a promising novel drug carrier for the controlled release of the poorly water-soluble drugs.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 춘계학술발표대회
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• pp.42-42
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• 2001

The objective of this study was to assess the development of porcine follicular oocytes fertilized by ICSI. Cumulus-oocyte-complexes (COCs) were collected by aspiration from follicles of 2-7 mm in diameter from a local slaughterhouse ovaries. Oocytes matured for 40-44 h were centrifuged at 12,000g for 6 min and then injected with sperm prepared by swim-up procedure in the presence or absence of 5 mM dithiothreitol (DTT). Injected oocytes were cultured in NCSU 23 medium during 6 to 8 days. IVF controls were compared to those of resulting embryos. The results obtained were as. follow: 1, The rates of cleavage and development rates into blastocyst by ICSI were not significantly (P<0.05) different between with (53.0% and 19.7%) or without (48.3% and 23.8%) centrifugation, respectively. 2. The cleavage and developmental rates to blastocyst after ICSI with or without 5mM DTT treated-sperm were not significantly (P<0.05) different (60.4% vs 16.4% and 48.5% vs 22.2%, respectively). 3. The cleavage and the developmental rates to blastocyst were not significantly (P<0.05) different between the zygotes obtained by IVF (51.8% vs. 22.4%) and ICSI (51.4% vs. 21.6%). 4. The number of blastomere in blastocyst stages after IVF or ICSI was not significantly different (46.7 $\pm$2.9 and 41.9$\pm$4.6).