• 제목/요약/키워드: comparative dissolution

검색결과 38건 처리시간 0.027초

Shmuel N. Eisenstadt and the Comparative Political History of Pre-Eighteenth-Century Empires

  • De WEERDT, Hilde
    • Asian review of World Histories
    • /
    • 제4권1호
    • /
    • pp.133-163
    • /
    • 2016
  • This essay critically analyses the legacy of Eisenstadt's The Political Systems of Empires for the comparative political history of pre-industrial empires. It argues that Eisenstadt has given us a rich toolkit to conceptualize the formation, maintenance, and dissolution of empires by theorizing the structural relationships between social groups in large-scale polities and among such polities, and by analysing global patterns of development in the distribution of the sources of social power. The Political Systems of Empires provides an inventory of key questions and dynamics that a comparative history of power relationships in empires cannot ignore. This essay, furthermore, discusses three methodological problems in Eisenstadt's work which have had a significant impact on comparative empire studies between the 1980s and the 2000s. The essay argues that certain shared features of comparative studies of pre-industrial empires help perpetuate Eurocentric analyses: the foregrounding of select empires and periods as ideal types (typicality), the focus on macro-historical structures and dynamics without the integration of social relationships and actions in historical conjunctures (the lack of scalability), and the search for convergence and divergence. These features need to be overcome to make Eisenstadt's legacy viable for comparative political history.

유기산 처리가 해도형 초극세 폴리에스터 섬유의 용출 특성에 미치는 영향 (1) (Accelerating Effect of Organic Acid Treatment on Weight Reduction Characteristics of Sea-Island Type PET Supermicrofiber (1))

  • 김혜인;정천희;민문홍
    • 한국염색가공학회지
    • /
    • 제24권1호
    • /
    • pp.45-53
    • /
    • 2012
  • In order to make a supermicrofiber fabric with PET/co-PET sea-island type filament fiber, the optimum conditions of dissolution of co-PET composite filament fiber was examined. The data set was made at various organic acid concentration and steam temperature with treated time as a main variable. At the same time, the microstructure changes by organic acid treatment of sea-island type PET supermicrofibers were monitored by thermal analysis morphology, DSC thermgrams and SEM images. Weight reduction behavior of supermicrofibers by caustic treatment was investigated in a comparative method. The termination of dissolution was also confirmed using DSC thermgrams and SEM images.

내포체 단백질 재생을 위한 용해 및 재접힘공정의 비교분석 (Comparative Analysis of Dissolution and Refolding Processes for Inclusion Body Protein Renaturation)

  • 김창성;김윤하;이은규
    • KSBB Journal
    • /
    • 제13권2호
    • /
    • pp.133-140
    • /
    • 1998
  • Using rlFN-$\alpha$ and rhGH as the model proteins, the refolding performances of the published processes were evaluated and compared. Key engineering parameters such as the type of denaturant and this concentration, protein concentration in the refolding buffer, and pH and ionic strength of the buffer were experimentally investigated. Furthermore, the role of a co-solvent of surfactant type in aggregation reduction was also studied. Of the denaturants tested (8M urea, 6M guanidine HCI, 0.5% SDS), SDS at alkaline pH (9.5) and ambient temperature gave the highest recovery yield. The SDS process was effective in the refolding of observed where dissolution proceeded better under lower strength (10 mM) but aggregation was suppressed under higher strength (>50 mM.) When PEG-4000 and/or Tween were added as co-solvent or refolding-enhancing additive, 1.6-2 times higher yield was realized. The‘masking’of the hyrophobic patches located on the surface of the protein with the surfactant molecules was believed to be responsible for the considerable reduction in aggregation during refolding.

  • PDF

아토르바스타틴 칼슘 고체분산체의 특성화 및 용출율 개선 (Improved Dissolution and Characterization of Solid Dispersed Atorvastatin Calcium)

  • 이준희;구정;박정수;박종학;안식일;모종현;김윤태;이종문;이해방;강길선
    • Journal of Pharmaceutical Investigation
    • /
    • 제38권2호
    • /
    • pp.111-117
    • /
    • 2008
  • To overcome the solubility of poorly water-soluble drug, the formation of solid dispersion using a spray-dryer with polymeric material, that can potentially enhance the dissolution rate extend of drug absorption was considered in this study. $Eudragit^{(R)}$ E100 as carrier for solid dispersion is acrylate copolymer that soluble in acidic buffer solutions (below pH 5.0). It was used to increase dissolution of atorvastatin calcium as a water-insoluble drug in acidic environments. In this study, a spray-dryer was used to prepare solid dispersion of atorvastatin calcium and $Eudragit^{(R)}$ E100 for purpose of improving the solubility of drug. Atorvastatin calcium and $Eudragit^{(R)}$ E100 were dissolved in ethanol and spray-dryed. DSC and XRD were used to analyze the crystallinity of the sample. It was found that atorvastatin calcium is amorphous in the $Eudragit^{(R)}$ E100 solid dispersion. FT-IR was used to analyze the salt formation by interaction between atorvastatin calcium and $Eudragit^{(R)}$ E100. Comparative dissolution study exhibited better dissolution characteristics than the commercial drug ($Lipitor^{(R)}$) as control. The dissolution rate of atorvastatin calcium was markedly increased in solid dispersion system in simulated gastric juice (pH 1.2). This study proposed that this solid dispersion system improved the bioavailability of poorly water-soluble atorvastatin calcium.

In vitro Dissolution and in vivo Bioequivalence Study of Controlled Release Carbamazepine Formulation (Epileptol CR® vs Tegretol CR® in Healthy Male Korean Volunteers

  • Kim, Ji-Young;Kim, Hyung-Tae;Kim, Chong-Kook
    • Journal of Pharmaceutical Investigation
    • /
    • 제38권5호
    • /
    • pp.335-342
    • /
    • 2008
  • The bioequivalence of two carbamazepine preparations was conducted. The in vivo bioequivalence study in 20 healthy male Korean volunteers was designed by using a single dose, randomized, 2-period crossover with a 3-weeks washout period between the doses. Prior to the in vivo study, an in vitro comparative dissolution test was performed by the paddle and basket method as described in the bioequivalence guidance of the Korea Food and Drug Administration (KFDA). Based on the similar dissolution pattern between two preparations in the dissolution test, the two formulations are demonstrated to be pharmaceutically equivalent. In addition, in vivo bioequivalence test was used to reconfirm the in vitro dissolution results. In the in vivo bioequivalence study, the plasma concentrations of carbamazepine up to 144 h after the administration were determined using a validated HPLC method with UV detection and the bioequivalence between the two drug products was assessed by statistical analysis of the log transformed mean ratios of $C_{max}$, $AUC_{0-t}$ and $AUC_{0-\infty}$. The mean maximum concentration ($C_{max}$) of the test and reference were found to be $1467.0{\pm}335.8\;ng/mL$ and $1465.9{\pm}310.3\;ng/mL$, respectively. The 90% confidence intervals (C.I.) of $C_{max}$ were in the range from 0.95 to 1.05. As for the $AUC_{0-t}$ and $AUC_{0-\infty}$, test values were $110027.1{\pm}27786.4\;ng/mL{\cdpt}h$, $128807.0{\pm}34563.2\;ng/mL{\cdot}h$ and $105473.6{\pm}26496.2\;ng/mL{\cdot}h$, $125448.5{\pm}35975.5\;ng/mL{\cdot}h$, respectively. The 90% C.I. of $AUC_{0-t}$ were 0.97 to 1.10 and of $AUC_{0-\infty}$, 0.99 to 1.09 and thus were within the log 0.8-log 1.25 interval proposed by the KFDA. A two-way ANOVA showed no significant difference between the two formulations. Based on these statistical analysis, it was concluded that the test formulation is bioequivalent to the reference.

대수층 지질 및 온도에 따른 국내 지하수의 지구화학적 특징 -화강암질암내 지하수와의 비교연구 (Geochemical Characteristics of Groundwater in Korea with Different Aquifer Geology and Temperature -Comparative Study with Granitic Groundwater)

  • 이종운;전효택;전용원
    • 대한지하수환경학회지
    • /
    • 제4권4호
    • /
    • pp.212-222
    • /
    • 1997
  • 국내 화강암질암내 지하수와의 대수층 지질 및 온도에 따른 지구화학적 특징 차이를 살펴보기 위하여 변성퇴적암류내 지하수와 온천수를 택하였다. 변성퇴적암류를 대수층으로 하는 지하수 내의 $Na^+$ 함량은 화강암질암에 비하여 통계적으로 낮다. 또한 화강암질암의 지하수와는 달리 변성퇴적암류의 지하수는 심부에서도 방해석의 거동에 의해 지하수의 화학조성이 조절됨으로써 $Ca^{2+]$-${HCO_3}^-$ 유형에 속한다. 이는 변성퇴적암류의 대수층 암석에 사장석의 함유량이 극히 적은 것에 기인한다. 요인분석 결과, 변성퇴적암류의100~300 m 심도의 지하수는 1) 방해석 및 Mg-탄산염암의 용해, 2) 백운모의 용해에 의하여 kaolinite가 illite로 전환되는 반응, 3) 지표에서 유입된 형태로 존재하는 $Na^+$ 등의 세 가지 요인으로 압축된다. 화강암질암과 변성퇴적암류에 대하여 도출된 판별함수는 약 81.8%의 판별력을 보였으며 이 판별식에 사장석이 주구성광물로 존재하는 화산암질 지하수를 적용한 결과 모두 화강암질암 그룹에 속하였다. 한편 온천수는 상대적으로 심도가 낮음에도 불구하고 화강암질암의 심부지하수와 유사한 화학적 특징을 보임으로써 고온으로 인해 주변 광물과의 반응이 활성화되었음을 나타낸다.

  • PDF

경상북도 일반고 위기학생의 지원 현황과 대책 (The Study of Current Situation and Policy Tasks of At-risk Student Support Policy in Gyeongsangbuk-do)

  • 김영환
    • 비교교육연구
    • /
    • 제24권3호
    • /
    • pp.47-69
    • /
    • 2014
  • 청소년기의 발달적 특성, 가족의 해체, 빈곤, 학업 스트레스 등으로 위기학생이 증가하고 있다. 이러한 위기상황은 학생 개인뿐만 아니라 사회전체에 역기능적인 영향을 미칠 가능성이 높다. 본 연구에서는 위기학생의 발생의 원인을 고찰하고 경상북도에서 시행되고 있는 위기학생 관리 지원체제 현황을 바탕으로 경상북도 위기학생 지원정책의 개선방향을 도출하였다. 경상북도의 위기 학생 지원 전략을 분석을 토대로 보완방안은 첫째는 위기학생의 예방 및 조기발견체제 구축이며, 둘째는 발견된 위기학생을 지도하기 위한 교육안전망을 구축, 셋째, 가정 지역사회와의 연계로 설정하고 각 영역별 보완 방안을 제시하였다.

배뇨 장애 치료를 위한 실로도신과 솔리페나신 숙신산염 함유한 새로운 복합 정제 개발 (Development of a novel combination tablet containing silodosin and solifenacin succinate for the treatment of urination disorder)

  • 최형주;이정균;김경수
    • 한국산학기술학회논문지
    • /
    • 제22권3호
    • /
    • pp.323-332
    • /
    • 2021
  • 본 연구의 목적은 배뇨장애 치료를 위한 실로도신과 솔리페나신 숙신산염을 함유한 새로운 복합 정제를 개발하는 것이다. 이러한 목표를 달성하기 위하여 실로도신과 솔리페나신 숙신산염의 동시 정량법을 확립하였다. 두 약물은 다양한 완충액에서 1 mg/ml 이상의 수용해도 값을 나타내었으며, 실로도신과 솔리페나신 숙신산염이 함유된 시판제품의 용출은 다양한 용출조건에서 30분 이내에 완료되었다. 시차 주사 열량계를 사용하여 부형제와 약물 간 상호 반응성을 확인하여 선정된, 약물과 반응성이 없는 부형제를 사용하여 습식 과립화 방법을 사용하여 결합제와 붕해제의 사용에 따른 다양한 처방을 제조한 후 용출시험을 진행하였다. 제조한 정제의 처방 중 실로도신, 솔리페나신 숙신산염, 유당, 미결정셀룰로오스 PH101, 소듐라우릴설페이트, 포비돈 K-30, 크로스포비돈 및 스테아린산마그네슘이 8/10/56/112/2/6/6/2(w/w)의 비율로 제조된 정제는 트루패스정(실로도신 시판 제품) 및 베시케어정(솔리페나신 숙신산염 시판 제품)과의 비교용출 시험시 동등성을 나타내는 것을 확인하였다. 따라서, 본 연구를 통해 얻어진 복합 정제는 각 약물의 시판 제품과 동등한 생체이용률을 나타낼 수 있을 것으로 판단되며, 향후 배뇨 장애 치료에 복약순응도가 우수한 의약품으로 활용될 수 있을 것으로 사료된다.

Living for the Children: Immigrant Korean Mothers' Re-creation of Family after Marital Dissolution

  • Oh, Seieun
    • 성인간호학회지
    • /
    • 제26권4호
    • /
    • pp.479-487
    • /
    • 2014
  • Purpose: This study was a grounded theory research aimed at generating a substantive theory that accounts for the explanatory social processes in which immigrant Korean single-mother families were engaged in the United States. Methods: In-depth interviews were conducted with 15 immigrant Korean single mothers who were living with children under 18 years of age at the time of the interviews. Data collection guided by theoretical sampling and concurrent constant comparative analysis of the transcribed data was conducted to identify the core social process. Results: The emerged core social process was "living for the children," which represented the driving process by which these women made transition to their new lives as single-mother families. The major task throughout the entire transition was re-creating their families. The women's transition involved practical and psychological transitions. The practical transition involved three stages: assuring family survival, struggling between the father role and the mother role, and stabilizing. The psychological transition involved becoming strong and settling in with a new supportive network. Conclusion: Study results added to the literature by elaborating the women's emphasis on maternal identity and the resilience-provoking nature of the women's transitions.