• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.10-24
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• 2013

The state-of-arts of multiscale simulation (MSS) in science and engineering is briefly presented and MSS for process development (PD-MSS) is proposed to effectively apply the MSS to the process development. The four-level PD-MSS is composed of PLS (process-level simulation), FLS (fluid-level simulation), mFLS (microfluid-level simulation) and MLS (molecular-level simulation). Characteristics and methods of each level, as well as connectivity between the four levels are described. For example in PD-MSS, absorption column, fluidized-bed reactor, and adsorption process are introduced. For successful MSS, it is necessary to understand the multiscale nature in chemical engineering problems, to develop models representing physical phenomena at each scale and between scales, to develop softwares implementing mathematical models on computer, and to have strong computing facilities. MSS should be performed within acceptable accuracy of simulation results, available computation capacity, and reasonable efficiency of calculation. Macroscopic and microscopic scale simulations have been developed relatively well but mesoscale simulation shows a bottleneck in MSS. Therefore, advances on mesoscale models and simulation tools are required to accurately and reliably predict physical phenomena. PD-MSS will find its way into a sustainable technology being able to shorten the duration and to reduce the cost for process development.

• Journal of The Korean Association For Science Education
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• v.31 no.2
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• pp.256-270
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• 2011

This study was designed to explore how learners' participation develop if provided with opportunities for various scientific practices and experiences in writing science magazine articles as an extra-curricular club activity and what factors facilitate these participation development. Data from participant observations, in-depth interviews with students, and documents were used to extract the common characteristics of the practices. The learners' development was categorized into 3 stages in terms of participation in the community of practice: peripheral participation, transitional participation, and full participation. As participation develops, situational interest developed to individual interests and value attachment. Students sought to get ideas from every day life, and finally, in the stage of full participation, advances in writing showed the characteristics of knowledge transformation. Best of all, the participants enjoyed and valued their participation showing identities as journalists. The nature of science magazine article, external scaffolding, and internalization through enjoyment and value attachment appeared to be decisive factors that facilitate the development of participation. Student's enculturation of writing for learning offers a possibility that continue to do so, even after they have left formal schooling and make a basis for lifelong learning.

• Journal of Oriental Medical Thermology
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• v.1 no.1
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• pp.28-37
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• 2002

Stable Compression Fractures(SCF hereafter) are most often caused by trauma such as traffic accidents. These SCFs usually occur in the thoracic and lumbar regions of the spinal cord. Human life spans have increased as a result of medical advances, which in turn has led to an increase in the elderly population. SCFs are divided into the categories of stable and unstable. The categories are determined through X-rays and P/Ex tests. The D.I.T.I. is then used to diagnose the severity and prognosis of the fracture injuries, and it allows an objective evaluation of the symptoms. This author researched 40 patients who were treated at Wonkwang University Oriental Medical Center from October 1995 to December 1996. The patients were diagnosed by X-ray as having SCFs and treated primarily with acupuncture. Both the changes in D.I.T.I. and patients' self-diagnoses of their conditions before and after treatment yielded the meaningful results which have been presented here. 1. 75% of those who suffer from Stable Compression Fractures are 60 years of older. Of those, the ratio of male to female is 1 to 4. This is due in part to the fact that many elderly women seek Oriental medicine treatment for conditions associated with advanced age. 2. 53.3% of these injuries occurred between T11 and L2. 3. 65% of patients were hospitalized for 10 to 29 days, and then able to be treated on an outpatiens basis. 4. The D.I.T.I. results showed 50% below $0.2^{\circ}C$, 30% between 0.3 and $0.5^{\circ}C$, 10% between 0.5 and $0.7^{\circ}C$, 10% between 0.7 and $0.9^{\circ}C$, and 0% over $0.9^{\circ}C$. 5. The results of treatment using Modified Evaluation System in Thoracolumbar Vertebral Fractures Method showed that 55% of patients achieved excellent recovery and 40% achived good recovery. After comparing the D.I.T.I. results before and after treatment, we found 50% of patients showed excellent recovery $({\Delta}T{\leq}0.2)$ and 40% showed good recovery$(0.2<{\Delta}T{\leq}0.5)$.

• Journal of Periodontal and Implant Science
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• v.33 no.2
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• pp.259-269
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• 2003

The ideal goal of periodontal therapy is the regeneration of periodontal tissue repair of function. Although is very difficult to attain the goal, recent advances in periodontal wound healing concepts encourage hope reaching it. Recently many efforts are concentrated on the regeneration potential of material used in traditional Korean medicine. Phlomidis Radix has been used for the treatment of blood stasis, bone fracture and osteoporosis in traditional Korean medicine. The purpose of this study is to examine effects of dichloromethane fraction Phlomidis Radix on Bone Formation in Human Fetal Osteoblasts. Human fetal osteoblastic cell line(hFOB1 1.19 ;American Type Culture Collection, Manassas, VA) were used and cells were cultured containing DMEM and dichloromethane fraction Phlomidis Radix(100 ng/ml , 1 ${\mu}$/ml, 10 ${\mu}$/ml) at 34$^{\circ}C$ with 5% $CO_2$ in 100% humidity. MTT was performed to examine the viability of the cell, and alkaline phosphatase activity was analyzed to examine the mineralization. Also bone calcification nodules were evaluated. The cellular activity of hFOB1 was increased in 100 ng/ml, 1 ${\mu}$/ml , 10 ${\mu}$/ml of dichloromethane fraction of Phlomidis Radix and especially significant increation was showed in 100 ng/ml of dichloromethane fraction of Phlomidis Radix at 6days (p <0.05). ALP level of hFOB1 was significantly increased in 100 ng/ml , 1 ${\mu}$/ml, 10 ${\mu}$/ml of dichloromethane fraction of Phlomidis Radix and especially more increation was showed in 10 ${\mu}$/ml of dichloromethane fraction of Phlomidis Radix (p <0,05). Calcification nodules of hFOB1 significantly increased in 10 ${\mu]$/ml of dichloromethane fraction of Phlomidis Radix at 21 days of incubation(p<0.05). The results indicate that dicholoromethane fraction of Phlomidis Radix has excellent effects on mineralization of hFOB1.

• Advances in pediatric surgery
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• v.7 no.2
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• pp.105-111
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• 2001

To investigate the diagnostic accuracy and applicability of barium enema(BE) and rectal suction biopsy with acetyl cholinesterase(AChE) histochemistry in the diagnosis of neonatal Hirschsprung's disease(HD), we retrospectively reviewed the findings of BE and AChE staining in 96 neonates with suspected HD during a 10-year period from January 1991 to December 2000. Sixty-nine cases of HD(58 males and 11 females) and 27 cases of non-HD are included in this study. In regard to BE, HD was based on definite transitional zone, suspicious HD on reversed rectosigmoid index(RSI <1), and non-HD on normal RSI(RSI>1). The histochemical criterion used for the diagnosis of HD was that of Chow et al(1977), i.e., the presence of many coarse discrete cholinergic nerve fibers in the muscularis mucosae and in the immediately subjacent submucosa regardless of infiltration of cholinergic nerve fibers in the lamina propria. Of 66 neonates with HD who underwent BE, transitional zone was identified in 33 cases(50 %) and reversed RSI in 19 cases(21 %), microcolon in 4 cases and normal finding in 10 cases(15 %) while of 27 neonates with non-HD, there was normal finding in 16 cases and reversed RSI in 9 cases(41 %). Thus diagnostic accuracy based on transitional zone was 64 %. The positive predictive value of reversed RSI for the diagnosis of HD was 68 %. Of 42 neonates with HD who underwent AChE histochemistry, there were 41 AChE-positive reactions and one AChE-negative reaction in a neonate with total colonic aganglionosis, while of 27 cases of non-HD, there were one equivocal AChE-positive reaction and 26 AChE-negative reactions. Thus AChE histochemical study showed a 97 % diagnostic accuracy with a 98 % sensitivity and a 96 % specificity. In conclusion, we believe that BE is valuable as a first diagnostic step since about 80 % of neonates with HD show significant radiologic findings such as a transitional zone or reversed RSI. AChE histochemical study was a more reliable diagnos tic tool showing a 97 % diagnostic accuracy, and is part.

• Advances in pediatric surgery
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• v.7 no.2
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• pp.95-104
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• 2001

Biliary atresia (BA) is very difficult to distinguish from neonatal hepatitis (NH) and its prognosis depends on the age at the time of Kasai operation. Therefore early differentiation between these two conditions is very important. Although various clinical and laboratory tests have been reported to differentiate between them, they are still of limited value. From 1980 to 1999, forty-five infants were referred to our pediatric surgical unit for operation for suspected BA. Eight patients underwent Kasai operation immediately because of late diagnosis. These were excluded from the study. The clinical history, physical findings. radiologic and laboratory examinations of 37 cases were analyzed retrospectively. The average age of BA (n=20) was $55.1{\pm}16.7$ days, and that of NH (n=17) was $55.8{\pm}15.6$ days. The sex ratio of BA was 13:7, and that of NH was 14:3. All the patients had obstructive jaundice and acholic stool except 4 BA and 6 NH patients. Acholic stool with yellow component was more frequent in NH. Onset of jaundice was within 2 weeks after birth in 85 % of BA, and in 65% of NH. The onset of acholic stool was within 2 weeks after birth in 60 % of BA, and in 23.5 % of NH. The duration of jaundice and acholic stool of BA were $50.9{\pm}16.6$ days and $41.3{\pm}18.4$ days and those of NH were $40.1{\pm}23.1$ days and $26.6{\pm}25.4$ days respectively. The ultrasonogram and hepatobiliary scan were useful, but not a definitively reliable method for the differentiation of these two diseases. There was no difference in laboratory data. Seventeen cases had NH among 45 referred cases for Kasai operation with the clinical impression of BA, and 4 cases of 17 NH cases needed to be explored to rule out BA. In conclusion. false positive rate of clinical impression of BA was 37.8 %. and negative exploration rate was 8.9 %, Therefore. careful clinical observation for 1-2 weeks by an experienced pediatric surgeon was very important to avoid unnecessary operation to rule out NH up to the age of 8 - 10 weeks. so long as the stool had yellow component.

• Advances in pediatric surgery
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• v.3 no.2
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• pp.98-107
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• 1997

To determine whether bile juice exclusion can prevent the mucosal damage, and Insulin-like growth factor-I can promote mucosal regeneration in ischemia-reperfusion injury of the bowel, 39 weanling rats with 10 cm of Thiry-Vella loop were studied. Animal groups were; Control, BL(common bile duct ligation), IGF{insulin-like growth factor-I(IGF-I) infusion} and IGF-BL(combined treatment). IGF-I(1.5 mg/kg/day) was continuously delivered through a subcutaneously implanted miniosmotic pump. After 15 minutes of superior mesenteric artery clamping, a tissue specimen(P) was taken after 30 minutes of reperfusion. Intestinal continuity was restored to allow oral feeding. A specimen of main tract(M) and another of the Thiry-Vella loop(T) were collected for histomorphometry after 48 hours of reperfusion and free feeding. Villus size ratio(VSR), crypt depth(CD), crypt-depth/villus-height ratio(CVR) and injury score(IS) were measured in 15 consecutive villi. The postoperative mortalities of bile duct ligation groups(BL and IGF-BL) were higher than those of other groups. In control group, VSR of M was lower(P<0.05) than P or T, but not in the other groups. VSR of M in control was lower than those in other groups. CD of T in control, IGF and IGF-BL group were higher than those of M. CD of M and T showed gradual increments from control, IGF and IGF-BL group, respectively. CVR of M and T in IGF group were higher than those in control. CVR in IGF-BL group, T was higher than M, and M was higher than P. About IS, M of BL($20.1{\pm}2.5$) and IGF-BL($20.9{\pm}3.3$) groups were significantly lower than that of control($32.4{\pm}2.5$). These results suggest that the exclusion of bile juice reduces the severity of the reperfusion injury of the mucosa, by inability to activate pancreatic enzymes and IGF-I stimulates mucosal regeneration in injured bowel, and the effect is potentiated by bile juice exclusion.

• Advances in pediatric surgery
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• v.2 no.2
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• pp.119-128
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• 1996

The survey on branchial anomalies was conducted by Korean Association of Pediatric Surgeons. A total of 173 cases were reported, which were managed by 36 members and cooperators during the three years from January 1, 1993 through December 31, 1995. The following results were obtained by retrospective analysis of the 173 cases of branchial anomalies. The presenting symptoms were cervical mass in 101 cases, pit with or without discharge in 71, cervical abscess in 47 and respiratory difficulty in 3. The average age of the patients with cervical abscess was 52 months. Seventy(79%) of 89 patients with branchial anomalies and a cystic mass had their first clinical manifestations by 1 year of age, while 40(51%) of 78 patients with only a branchial cyst had their first clinical manifestation in first year of life. Radiologic studies were carried out in 77 patients (43%). The preferred diagnostic modalities were ultrasonography(47 patients), simple neck radiogram(19) and CT scan(17). Preoperative diagnosis was correctly made in 156(91%) of 173 patients. Seventeen patients were incorrectly diagnosed as thyroglossal duct cyst in 5 patients, cystic hygroma in 4, dermoid cyst in 3, and lymphadenopathy in 3. There were no remarkable difference in sex and laterality of presentation but bilateral lesions were found in 9(5%) patients and unusual locations of the anomalies were the manubrium, left subclavicular area, median cervial area, preauricular and parotid area. There were 78(45%) patients with cyst, 52(30%) patients with sinus, 35(20%) patients with fistula and 8(5%) patient with skin tag. Embryological classification was possible in only 64(37%) patients. The 2nd branchial anomaly was present in 50(78%), the 1st branchial anomaly in 10(18%), and the 3rd or 4th branchial anomaly in 4(6%). Histopathological study of the lining epithelium(N=134) is recorded that 45% were lined with squamous epithelium, 17% with respiratory epithelium, 6% with. squamous and respiratory epithelium, 14% with inflammatory change. Lymphoid tissue was common(62%) in the wall of the lesions. Twelve(7%) of 158 patients had postoperative complications including wound complication, recurrence and facial nerve palsy.

• Advances in pediatric surgery
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• v.10 no.2
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• pp.99-106
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• 2004

Intestinal atresia is a frequent cause of intestinal obstruction in the newborn. We reviewed the clinical presentation, associated anomalies, types of atresias, operative managements, and early postoperative complications in 36 cases of intestinal atresia treated at the Department of Surgery, Kyungpook National University Hospital between January 1994 and February 2003. Location of the lesion was duodenum in 17 patients, jejunum in 11 patients and ileum in 8 patients. The male to female ratio was 1:1.4 in duodenal atresia (DA), 2.7:1 in jejunal atresia (JA) and 7:1 in ileal atresia (IA). The most common type was type III (41.1 %) in DA, and type I (52.6 %) in JA and IA. The most common presenting symptoms was vomiting(88.2 %) in DA, but in jejunoileal atresia, vomiting(89.4 %) and abdominal distension(89.4 %) were the most common sign and symptom. All cases of DA were diagnosed by plain abdominal radiography. There were 6 cases of DA with congenital heart disease, 3 cases of DA with Down syndrome and 3 cases of JA with meconium peritonitis. Segmental resection was performed in 13 cases, duodenoduodenostomy in 11 cases, membrane excision in 7 cases, jejunojejunostomy in 2 cases, gastroduodenostomy in 2 cases and ileocolic anastomosis in 1 case. There were 9 postoperative complications including 3 each of anastomotic leakage, wound infection, and intestinal obstruction 3 cases. The mortality rate for DA was 11.8 %(2/17). Both deaths in DA were attributed to congenital heart disease. The mortality rate for JA was 18% (2/11). Both cases died with sepsis and short bowel syndrome.

• Advances in pediatric surgery
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• v.12 no.1
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• pp.53-69
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• 2006

This is a survey on congenital posterolateral diaphragmatic hernia, conducted by the Korean Association of Pediatric Surgeons(KAPS). A registration form for each patient during the 5-year-period between 1998 and 2002 and a questionaire were sent to each member. Twenty-ninemembers in 22 institutions returned completed forms. The average number of patients per surgeon was 1.4 cases a year. The male to female ratio was 1.64: 1, and annual incidencewas 1/14,522 live births. In this review, factors influencing survival in congenital posterolateral diaphragmatic hernia were age at admission, birth weight, time of antenatal diagnosis, birth place, Apgar score, onset time of symptoms and signs, preoperative cardiopulmonary resuscitation, associated anomalies of themusculoskeletal system, central nervous system, or chromosomes, preoperative stabilization, levels of preoperative $FiO_2$, pH, and $AaDO_2$, perioperative complications, bilaterality of defect, size of the defect, and presence or absence of hernia sac.