Changes in the Ångstrom Exponent during Aerosol Coagulation and Condensation

Jung, Chang H.,Lee, Ji Yi,Kim, Yong P. Korean Society for Atmospheric Environment 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

In this study, the ${\AA}$ngstrom exponent for polydispersed aerosol during dynamic processes was investigated. Log-normal aerosol size distribution was assumed, and a sensitivity analysis of the ${\AA}$ngstrom exponent with regards the coagulation and condensation process was performed. The ${\AA}$ngstrom exponent is expected to decrease because of the particle growth due to coagulation and condensation. However, it is difficult to quantify the degree of change. In order to understand quantitatively the change in the ${\AA}$ngstrom exponent during coagulation and condensation, different real and imaginary parts of the refractive index were considered. The results show that the ${\AA}$ngstrom exponent is sensitive to changes in size distribution and refractive index. The total number concentration decreases and the geometric mean diameter of aerosols increase during coagulation. On the while, the geometric standard deviation approaches monodispersed size distribution during the condensation process, and this change in size distribution affects the ${\AA}$ngstrom exponent. The degree of change in the ${\AA}$ngstrom exponent depends on the refractive index and initial size distribution, and the size parameter changes with the ${\AA}$ngstrom exponent for a given refractive index or chemical composition; this indicates that the size distribution plays an important role in determining the ${\AA}$ngstrom exponent as well as the chemical composition. Subsequently, this study shows how the ${\AA}$ngstrom exponent changes quantitatively during the aerosol dynamics processes for a log-normal aerosol size distribution for different refractive indices; the results showed good agreement with the results for simple analytic size distribution solutions.

Changes in the Angstrom Exponent during Aerosol Coagulation and Condensation

Chang H. Jung,Ji Yi Lee,Yong P. Kim,김용표 한국대기환경학회 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.4

In this study, the Ångstrom exponent for polydispersed aerosol during dynamic processes was investigated. Log-normal aerosol size distribution was assumed,and a sensitivity analysis of the Ångstrom exponent with regards the coagulation and condensation process was performed. The Ångstrom exponent is expected to decrease because of the particle growth due to coagulation and condensation. However, it is difficult to quantify the degree of change. In order to understand quantitatively the change in the Ångstrom exponent during coagulation and condensation,different real and imaginary parts of the refractive index were considered. The results show that the Ångstrom exponent is sensitive to changes in size distribution and refractive index. The total number concentration decreases and the geometric mean diameter of aerosols increase during coagulation. On the while, the geometric standard deviation approaches monodispersed size distribution during the condensation process, and this change in size distribution affects the Ångstrom exponent. The degree of change in the Ångstrom exponent depends on the refractive index and initial size distribution, and the size parameter changes with the Ångstrom exponent for a given refractive index or chemical composition; this indicates that the size distribution plays an important role in determining the Ångstrom exponent as well as the chemical composition. Subsequently, this study shows how the Ångstrom exponent changes quantitatively during the aerosol dynamics processes for a log-normal aerosol size distribution for different refractive indices; the results showed good agreement with the results for simple analytic size distribution solutions.

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

Changes in Spatiotemporal Parameters and Lower Limb Coordination During Prosthetic Gait Training in Unilateral Transfemoral Amputees

Yunhee Chang,Chang-Yong Ko,Bo Ra Jeong,Jung Sun Kang,Hyuk-Jae Choi,Gyoosuk Kim,Hyunjun Shin,Sehoon Park 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.23 No.3

When applying prosthetic gait training to patients with lower limb amputation, monitoring the gait change process is crucial for establishing and modifying rehabilitation training plans. In addition, since human gait involves complex movement of several joints, it is necessary to analyze the organic movement of adjacent joints rather than a single joint in the lower extremities for understanding the process of gait change. Therefore, this study aimed to analyze changes in spatiotemporal parameters and lower limb coordination during prosthetic gait training in unilateral transfemoral amputees (TFAs). This retrospective case–control study included 10 unilateral TFAs and 10 healthy individuals as controls. TFAs received prosthetic gait training for 12 weeks and gait changes were analyzed every 2 weeks using a 3D motion analysis system. The measured variables were spatiotemporal parameters and the continuous relative phase between hip and knee joints. The highest improvement in walking speed was seen at week 4 of training, and the continuous relative phase was most symmetric at week 8. The lower limb coordination pattern was more in-phase in the TFAs than in the controls, and the coordination variability was also lower for the TFAs than for the controls. In addition, the rate of change in lower limb coordination of TFAs was lower than that of spatiotemporal parameters and was significantly different from that of the controls even after training. Considering that the decrease in lower limb coordination is related to gait efficiency, balance, and risk of fall, there is a need to develop therapeutic strategies that can further improve the coordination of TFAs.

정신분열병 환자에서 가족력, 산과적 합병증 및 신체미세기형의 관련성에 관한 연구

안용민,김용식,정희연,신지용,윤세창,배안,이중서,주은정,이창인 大韓神經精神醫學會 1999 신경정신의학 Vol.38 No.2

연구목적 : 저자들은 태생기 동안에 받는 유전외적 요인, 즉 환경적 요인이 산발성 정신분열병 환자들의 발병에 크게 관여할 것이라고 가정하였다. 이를 검증하기 위하여 형제 중 1인 이상이 발병하여 가족력을 분명히 알 수 있는 정신분열병 환자군(이하 형제 환자군)과 가족력이 없는 산발성 정신분열병 환자군(이하 산발성 환자군) 및 정상대조군을 대상으로 산과적 합병증, 신체미세기형 및 정신분열병의 임상 양상을 비교하였다. 방 법 : 연구 대상은 형제 환자군 43명(남 22명, 여 21명), 산발성 환자군 43명(남 23명, 여 20명), 정상대조군 43명(남 20명, 여 23명)이었다. 산과적 합병증은 Lewis 척도를 이용하여 평가하였고 신체미세기형은 Waldrop 척도를 이용하여 측정하였다. 임상 양상으로서 발병 연령, 병전 기능 수준, 정신병리, 약물에 대한 반응, 회복시의 전반적 기능 수준, 지연성 운동장애의 유무를 평가하였다. 결 과 : 정상대조군과 정신분열병 환자군 전체를 비교하였을 때 산과적 합병증과 신체미세기형의 총점과 각 소항목의 점수에 차이가 없었다. 산발성 환자군과 형제 환자군을 비교하였을 때 산과적 합병증의 전체 점수에서는 유의한 차이가 없었으나, 출생 당시에 태아가 받은 스트레스 항목의 점수가 산발성 환자군에서 유의하게 높았다. 신체미세기형에서는 전체 점수 및 입의 미세기형 점수가 산발성 환자군에서 유의하게 높았다. 신체미세기형의 전체 점수가 4점 이상인 환자수도 산발성 환자군에서 높은 경향성을 보였다. 산과적 합병증과 신체미세기형 사이의 상호 연관성은 찾을 수 없었다. 정신분열병의 임상 양상 중에서는 Krawiecka 척도의 총점 및 양성 증상 점수와 회복시의 전반적 기능 수준만이 형제 환자군에 비해 산발성 환자군에서 유의하게 높았다. 성별에 따라서는 형제 환자군에서 남자 환자의 산과적 합병증이 유의하게 높았다. 결 론 : 본 연구를 통해 산과적 합병증 및 신체미세기형 연구가 정신분열병의 원인을 규명하기 위한 유용한 방법임이 시사되었지만, 가족력, 산과적 합병증 및 신체미세기형의 관련성에 대해서는 분명한 결론을 내리지 못하였다. The authors hypothesized that sporadic schizophrenic patients had more chances of receiving environmental insults during the fetal neural development compared with familial schizophrenics. We tested our hypothesis by comparing obstetric complications(OCs), minor physical anomalies(MPAs) and other clinical features, and examining the correlation between OCs and MPAs in schizophrenic patients who had one or more sibling with schizophrenia(sibling group) and sporadic schizophrenics(sporadic group) and normal controls. OCs were evaluated by the scale of Lewis, and MPAs were measured by the Waldrop scale. There were no significant difference in OCs and MPAs between schizophrenic and control groups. Sporadic group had significantly higher fetal distress, total Waldrop score and Waldrop score for mouth than sibling group. And there was a tendency that the number of subjects having the Waldrop score over 4 points was greater in the sporadic group. No significant correlation was observed between CCs and MPAs. The scores of initial psychopathology and post-treatment functioning were much higher in the sporadic group, but the other clinical feature showed no difference. Although male patients had more OCs than female patients in sibling group, no sex difference were observed as a whole. Our results suggest that, if the methodological weakness were complemented, OCs and MPAs would be useful tools in the search for the cause of schizophrenia.

비부비동 반전성 유두종의 전산화 단층촬영상과 자기공명영상의 분석

배창훈 ( Chang Hoon Bai ),서영중 ( Young Jung Seo ),이석춘 ( Seok Choon Lee ),천승민 ( Seung Min Chen ),백운회 ( Un Hoi Baek ),정은채 ( Eun Chae Jung ),송시연 ( Si Youn Song ),김용대 ( Yong Dae Kim ) 영남대학교 기초/임상의학연구소 2005 Yeungnam University Journal of Medicine Vol.22 No.2

Background: Computed tomography (CT) is commonly used to evaluate the degree of sinus involvement in cases of inverted papilloma (IP). However, CT cannot differentiate tumor from adjacent inflammatory mucosa or retained secretions. By contrast, magnetic resonance imaging (MRI) has been reported to be useful in distinguishing IP from paranasal sinusitis. This study investigated whether preoperative assessment with MRI and CT accurately predict the extent of IP.1) Materials and methods: CT and MRI were retrospectively reviewed in 9 cases of IP. Patients were categorized into stages based on CT and MRI findings, according to the staging system proposed by Krouse. The involvement of IP in each sinus was also assessed. Results: Differentiation of IP from inflammatory disease may be more successful in routine cases where the inflammatory mucosa has low signal intensity on T1-weighted images and very high signal intensity on T2-weighted images. CT imaging could not differentiate tumor from adjacent inflammatory mucosa or retained secretions. Conclusion: Preoperative MRI of IP can predict the location and extent of the tumor involvement in the paranasal sinuses and sometimes predicts malignant changes.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

항정신병약물 사용 중인 정신분열병 환자에서 올란자판으로의 교체 방법에 관한 연구(II) : Comparison of Safety 안전성 비교

안용민,권용실,권준수,민성호,박두병,양문정,소형석,송종호,신윤식,우행원,유범희,이홍석,정한용,한창환,김용식 大韓神經精神醫學會 2002 신경정신의학 Vol.41 No.5

연구목적: 이 다기관 공동임상연구는 사용 중인 항정신병약물을 ’직접 교체 방법’또는 ’시작-감량 교체 방법’중 한 가지 방법으로 올란자핀으로 교체한 후, 안정성 측면에서 두 교체 방법 간의 비교와 교체후의 변화를 관찰하기 위한 것이다. 방법: 국내 13개 병원의 입원 및 외래에 내원한 환자들 중 ICD-10 지단기준으로 정신분열병에 해당되며, 임상적으로 항정신병약물 교체가 필요한 환자를 대상으로 하였다. 두 가지 교체 방법 중 한 가지를 무작위로 피험자에 적용하였으며, ’직접 교체 방법’에 배정된 경우에는 사용중인 항정신병약물을 일시에 중단하고 10㎎의 올란자핀을 바로 투여하였고, ’시작-감량 교체 방법’에 배정된 경우는 10㎎의 올란자핀 투여하고 2주에 걸쳐서 기존 약물을 감량하여 중단하였다. 올란자핀 사용기간은 총 6주이며, 용량은 5∼20㎎ 범위로 제한하였다. 한정성 평가를 위해서 체중, 생명징후, 자발적인 이상반응 복, 실험실 검사 그리고 Simpson-Angus Scale(SAS), Barnes akathisia rating scale(BARS), Abnormal involuntary movement scale(AIMS). Liverpool University neuroleptic side effect rating scale(LUNSERS)등을 이용하였다. 결과: 총 103명의 정신분열병 환자를 대상으로 하였다. 사용한 올란자핀의 용량, 벤조디아제핀의 병용률, 탈락률과 탈락 사유, 자발적인 이상반응 보고, 생명징후, 실험실 검사 그리고 대부분의 부작용 척도 상에서 임상적으로 의미 있는 차이를 두 교체 방법간에 발견하지 못하였다. 다만 AIMS의 감소는 ’직접 교체 방법’군에서 보다 적었고, 항콜린제의 병용률은 ’시작-감량 교체 방법’군에서 보다 많았다. 기저 상태에서 전체 피험자의 SAS와 BARS 점수는 각각 3.5점과 1.8점이었으며 70% 이상의 피험자가 고프로락틴 혈증을 보였다. 올란자핀으로 교체한 후, SAS, BARS, AIMS 점수의 유의한 감소가 있었으며 고프로락틴 혈증을 보인 피험자 분율도 약 30%이하로 감소하였다. 그러나 교체 방법과 상관없이 올란자핀 교체 후 유의한 체중 증가가 있었다. 결론: 이 연구를 통해 교체 방법에 관계없이 비교적 안전하고 용이하게 올란자핀으로 교체 할 수 있음을 알 수 있었다. 그리고 기존 항정신병약물을 올란자핀으로 교체함으로써 일부 부작용들을 줄일 수 있음을 간접적으로 관찰할 수 있었다. 하지만 이 연구는 여러 제한점과 문제점을 지니고 있기 때문에 보다 체계적인 연구를 통해 검정이 필요하리라 생각된다. Objectives: This multicenter clinical trial involving 13 hospital sites compared the safely of switching to olanzapine between ’direct switching method’ and ’start-tapering switching method’. Method: This study included both inpatients and outpatients who fulfilled the criteria for schizophrenia as defined in the ICD-10, and were in need to be appropriate for switching antipsychotics. Subjects were randomly assigned to one of the two switching methods. For ’direct switching method’group, previous antipsychotics were abruptly discontinued and 10㎎ of olanzapine was administered, and previous antipsychotics was gradually tapered for 2 weeks. Olanzapine was used for 6 weeks and the dose was adjusted within the range of 5-20㎎. The safety of switching to olanzapine was measured with vital sings including body weight, adverse events reported spontaneously, laboratory tests, and various scales such as Simpson-Angus Scale(SAS), Barnes Akathisia Rating Scale(BARS). Abnormal Involuntary Movement Scale(AIMS), and Liverpool University Neuroleptic Side Effect Rating Scale(LUNSERS). Results: 103 patients were switched to olanzapine in this study. The comparison between two switching methods did not show any significant difference in the dosage of olanzapine used, the concomitant use of benzodiazepine, the rate and reasons of drop-out, the adverse events, vital signs, laboratory tests, and most scales for measuring side-effects. However, the decrease in AIMS scores was significantly lower in ’direct switching method’ group, and the concomitant use of anticholinergics was comparatively greater in ’start-tapering switching method’ group. At baseline, SAS and BARS scores were 3.5 and 1.8 points respectively, and more than 70% of the subjects showed hyperprolactinemia. After switching to olanzapine, SAS, BARS, and AIMS scores were significantly decreased and the proportion of the patients with hyperprolactinemia was also decreased to less than 30%. However significant weight gain after the treatment of olanzapine was observed regardless of switching method. Conclusion: This study may suggest that switching to olanzapine can be done with relatively high safety regardless of switching methods and olanzapine can significantly decrease some side-effects induced by other antipsychotics.

Ischemia-Related Changes in Galanin Expression in the Dentate Hilar Region after Transient Forebrain Ischemia in Gerbils

LEE, Hyeon Yong,HWANG, In Koo,KIM, Dae Ho,KIM, Jung Hwa,KIM, Chang Ho,LIM, Beong Ou,KANG, Tae-Cheon,BANG, Kyung Hwan,SEONG, Nak Sul,LEE, Hak Ju,KIM, Jong Dai,WON, Moo Ho Japanese Association for Laboratory Animal Science 2005 EXPERIMENTAL ANIMALS Vol.54 No.1

<P>Although galanin (GAL) protects hippocampal neurons from ischemic damage, no study has examined ischemia-related changes in endogenous GAL in the hippocampal dentate gyrus. We investigated the chronological changes of GAL, well-known as the potassium channel opener, expression in the dentate gyrus at various times after 5 min of transient forebrain ischemia in gerbils. A few GAL-immunoreactive (IR) neurons were found in the polymorphic layer of the sham-operated group. Three hours after ischemia-reperfusion, the pattern of GAL immunoreactivity was similar to that of the sham-operated group and the number of GAL-IR neurons and immunoreactivity were highest 12 h after ischemic insult. At this time, GAL-IR neurons in the polymorphic layer showed strong GAL immunoreactivity. Thereafter, GAL-IR neurons and immunoreactivity significantly decreased in the dentate hilar region. Four days after ischemic insult, GAL-IR neurons were not detectable. In addition, the results of a Western blot study showed a pattern of GAL expression similar to the immunohistochemical changes. GAL protein content also was highest 12 h after ischemia. In conclusion, the increased expression of endogenous GAL in the dentate gyrus after ischemia is related to response to the ischemic damage.</P>

General Equilibrium Model of Economic Growth and Structural Change in Agriculture

Park, Jung Keun,Kang, Chang Yong 전북대학교 농업과학기술연구소 1984 農大論文集 Vol.15 No.-

經濟構造의 變化는 最終需要나 中間財需要等 需要條件의 變化에 따라 說明되기도 하고 資源, 技術 等 供給條件의 變化에 따라 論明되기도 한다. 그러나 需要·供給條件의 相五聯關性을 따른 經濟購造變化의 說明이 가장 바람직하다고 할수 있다. Tolley-Smidt, Kelley- williamson, Yamaguchi-Binswanger等은 經濟構造 變化를 一般均衡模型에 의하여 分析하였다. 그들의 模型은 모두 農業部門의 二部門 模型에 基礎를 둔다. 그러나 開發途上國의 經濟成長에 따른 農業內部의 構造變化는 食糧部門과 非食糧部門의 特性을 뚜렷하게 區分짓기 때문에 經濟成長과 構造變化는 食糧部門, 非食糧部門, 非農業部門의 三部門模型에 의하여 接近할 必要가 있다. 本硏衆 이와 같은 問題點에 立脚하여 Yamaguchi-Binswanger 部門 模型을 三部門模型으로 延長, 擴大코저 한다. A selective review of the hypotheses purporting to explain the structural changes of economy reveals the structure of final or intermediate demand as a key explanation of structural change, while others suggest that any model purporting to explain this phenomenon should explore differences in production technologies, factor substitution possibilities and rate of technical change. However, the critical importance of interdependence between demand and supply condition naturally leades to general equilibrium model. Tolley-Smidt, Kelley-Williamson, and Yamaguchi-Binswanger analyzed the structural change with general equilibrium condition under the two sector (agriculture and industry) model. However, for most developing countries the structural change within agriculature can be observed as a result of the rapid economic growth. In the light of this point, this study is an attempt to analyze the economic development in terms of vital relationship within agriculatural sectors (food grain and non-food grain) and between these sectors and industry and to extend Yamaguchi-Binswanger model to three sector model.