• Title/Summary/Keyword: Stabilization conditions

Search Result 485, Processing Time 0.032 seconds

Evaluation of analgesic and antiinflammatory activity of Ophiorrhiza nicobarica, an ethnomedicine from Nicobar Islands, India

  • Chattopadhyay, Debprasad;Das, Sonali;Mandal, Asit Baran;Arunachalam, G;Bhattacharya, SK
    • Advances in Traditional Medicine
    • /
    • v.7 no.4
    • /
    • pp.395-408
    • /
    • 2007
  • This study reports the analgesic, anti-inflammatory and membrane-stabilizing property of alcoholic extract of Ophiorrhiza nicobarica (ON), a wild herb, used as an anti-infective ethnomedicine of Nicobarese and Shompen tribes of Great Nicobar Island, India. We for the first time investigated the analgesic and antiinflammatory potential of this herb in acute, subacute and chronic model of inflammation in Swiss albino mice and Wistar albino rats, along with sheep RBC-induced sensitivity and membrane stabilization. The acetic acid induced writhing, tail flick and tail immersion tests are used as a model for evaluating analgesic activity; while the carrageenin-induced paw oedema was used as the model for acute inflammation, dextran-induced oedema as sub-acute and cotton-pellateinduced granuloma as chronic inflammatory model. The probable mode by which ON mediate its effect on inflammatory conditions was studied on sheep RBC-induced sensitivity and membrane stabilization. The in vitro results revealed that the ON extract possesses significant (P < 0.05) dose dependent analgesic and antiinflammatory activity at 200 and 300 mg/kg and its fractions at 50 mg/kg, p.o. respectively, compared to the control groups. However, the extract failed to exhibit membrane-stabilizing property as it unable to reduce the level of haemolysis of RBC exposed to hypotonic solution. The acute toxicity studies of ON extract in rats and mice revealed that the extract was nontoxic even up to 3.0 g/kg body weight of the animals, with a high safety profile. We have isolated ursolic acid, ${\beta}$-sitosterol and harmaline respectively, from the bioactive part of the extract. The results indicated that the O. nicobarica is indeed beneficial in primary health care, and suggest that its anti-inflammatory activity may not be related to membrane-stabilization.

Spin-Stabilization for the Second Stage of Korea Sounding Rocket-III (KSR-III 탑재부 스핀안정화 기법 연구)

  • Sun, Byung-Chan;Choi, Hyung-Don
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.30 no.7
    • /
    • pp.137-143
    • /
    • 2002
  • This paper concerns the spin-stabilization for the second stage of KSR-III(Korea Sounding Rocket-III). The error sources in the second stage are defined, and then the effect on attitude error of KSR-III is analyzed quantitatively and qualitatively. Based on the analysis, some conditions for optimal spinning frequency and optimal steady-spinning duration are suggested. Among several solutions, an optimal value can be determined in the point of minimum impact-point error. An approach to a sub-optimal solution is also suggested. Application to the KSR-III shows that a proper spinning frequency and a steady-spin duration to give the smallest impact-point error can be effectively determined.

Process Optimization for Preparing High Performance PAN-based Carbon Fibers

  • Yun, Jeong-Hyeon;Kim, Bo-Hye;Yang, Kap-Seung;Bang, Yun-Hyuk;Kim, Sung-Ryong;Woo, Hee-Gweon
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.10
    • /
    • pp.2253-2258
    • /
    • 2009
  • wet spun polyacrylonitrile (PAN) fiber precursors. The process variables chosen were treatment temperature, applied tension in stabilization process. The temperature profile of the stabilization was set on the basis of exothermic peaks of the differential scanning calorimetry (DSC) result. Both tensile strength and modulus increased with holding at onset temperatures of the exothermic peaks for extended duration, and with a higher heating rate up to the onset temperatures at a given applied tension among the experimental conditions. The increase in load monotonously increased the tensile modulus, on the other hand, the tensile strength was maximum at the load of 15 mg/filament (T15). The load 20 mg/ filament (T20) was considered to be exceeded to form oriented crystalline structure, possibly introducing more defects in the fiber than under load of T15. The sample CP3-T15 O5 H30 showed the best tensile properties among the samples experimented whose tensile properties are compatible with the commercialized grade of general purpose carbon fibers even at low carbonization temperature such as $800\;{^{\circ}C}$ (the carbonization temperature in the commercial process. 1300∼$1500\;{^{\circ}C}$).

Risk Mitigation Measures in Arsenic-contaminated Soil at the Forest Area Near the Former Janghang Smelter Site: Applicability of Stabilization Technique and Follow-up Management Plan ((구)장항제련소 주변 송림숲 등 식생지역에서의 비소오염토양 위해도 저감 조치: 안정화 공법 적용성 평가 및 사후관리 계획)

  • An, Jinsung;Yang, Kyung;Kang, Woojae;Lee, Jung Sun;Nam, Kyoungphile
    • Journal of Soil and Groundwater Environment
    • /
    • v.22 no.6
    • /
    • pp.1-11
    • /
    • 2017
  • This study was conducted to investigate the performance of four commercial chemical agents in stabilizing arsenic (As) in soil at the forest area near the former Janghang smelter site. After amending the stabilizing agents (A, B, C, and D) into As-contaminated soil samples, synthetic precipitation leaching procedure (SPLP) and solubility bioavailability research consortium (SBRC)-extractable As concentrations significantly decreased except for agent D, which is mainly composed of fly ash and calcium carbonate. Increase of SPLP and SBRC-extractable As concentrations in four soil samples (S1, S2, S3, and J2) was attributed to desorption of As adsorbed on iron oxides due to high pH generated by agent D. It is therefore necessary to consider application conditions according to soil characteristics such as pH and buffering capacity. Results of sequential extraction showed that readily extractable fractions of As in soil (i.e., sum of $SO_4-$ and $PO_4-extractable$ As in soil) were converted into non-readily extractable fractions by amending agents A, B, and C. Such changes in the As distribution in soil resulted in the decrease of SPLP and SBRC-extractable As concentration. A series of follow-up monitoring and management plan has been suggested to assess the longevity of the stabilization treatments in the site.

The Effect of Dynamic Neuromuscular Stabilization Exercise on Pulmonary Function and Electroencephalogram in Elderly (동적 신경근 안정화 운동이 노인들의 폐기능과 뇌파에 미치는 영향)

  • Ho-Kwan Ko;Seung-Chul Chon
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.12 no.3
    • /
    • pp.25-36
    • /
    • 2024
  • Purpose : After coronavirus disease 2019 pandemic, many people around the world became aware of respiratory diseases and developed increased interest in health and exercise. As the elderly population grows larger, the prevalence of brain diseases and respiratory conditions increases. This study aimed to investigate the impact of dynamic neuromuscular stabilization (DNS) exercises on pulmonary function and electroencephalogram (EEG) findings in the elderly population. Methods : In this study, we measured the pulmonary function and performed EEG of 30 elderly individuals. The participants were randomly divided into an experimental group (n=15) and a control group (n=15). The experimental group completed a DNS exercise training protocol, while the control group performed simple exercise training. After the exercise, the pulmonary function and EEG testing were repeated, and the amounts of change within and between groups were determined. Results : In terms of pulmonary function, the experimental group's forced vital capacity (FVC) and forced expiratory volume at 1 second (FEV1) increased significantly after the exercise (p<.05), while the FVC differed significantly between groups (p<.05). In terms of EEG findings, the relative alpha waves significantly decreased in the F3 region (p<.05), while the relative beta waves significantly increased in the F4 region (p<.05). The relative gamma waves increased significantly in the Fp2 and P3 regions (p<.05), while the values in the F3 region differed significantly between groups (p<.05). Conclusion : DNS exercises performed by this elderly population demonstrated significant clinical value by providing fundamental data about both pulmonary function and EEG activity.

The Chewing Efficiency of Occlusal Stabilization Appliances by Anatomy of the Occlusal Surface (교합안정장치 교합면의 모양에 따른 저작효율)

  • Im, Yeong-Gwan;Choi, Choong-Ho;Kim, Jae-Hyeong;Rhee, Chong-Ouk;Kim, Byung-Gook
    • Journal of Oral Medicine and Pain
    • /
    • v.30 no.3
    • /
    • pp.361-373
    • /
    • 2005
  • Occlusal appliance therapy has been proven to be very useful and effective in reducing signs and symptoms of patients with TMD. However, there are no reports about the masticatory efficiency of the occlusal appliance. The purpose of this study was, first, to investigate the masticatory efficiency of the conventional stabilization appliance experimentally in normal healthy subjects, by comparing it with that of their natural dentition; and, second, to develop a modified stabilization appliance as an attempt to increase masticatory efficiency. Eleven subjects (mean age 25.3 years, range from 23 to 33) participated in this study. Six were men and five were women. They were healthy and had complete or near―complete natural dentition, and did not present with signs or symptoms of TMD. Two kinds of occlusal appliances―the conventional flat maxillary stabilization appliance (i.e., FSA) and a modified maxillary stabilization appliance with additional anatomic structures on its occlusal surface (i.e., ASA)―were made for every subject. Subjects chewed peanuts that were selected as a food to test the three masticatory conditions of the natural dentition, the ASA, and the FSA. The number of chewing strokes was counted during each 1-minute chewing period. Chewed peanut boluses were recovered and their hardness was measured by texture analysis. Statistical tests were performed. The following results were obtained. 1. The masticatory efficiency of the FSA was 38.6 percent that of the natural dentition. The efficiency of the ASA was 78.2 percent that of the natural dentition. 2. The number of chewing strokes in the natural dentition condition was measured to be 1.5 strokes per second. It decreased to 90 percent in the ASA and FSA conditions. These results indicate that the ASA could serve an improved masticatory capacity as well as its therapeutic effects in TMD. A clinical application of the ASA should be considered to extend the management of TMD patients.

Vegetation survey in nature-friendly small streams for each protection method (자연형 소하천의 호안공법별 식생분포 조사)

  • Lee, Kang-Suk;Park, Jin-Ki;Yeon, Gyu-Bang;Park, Jong-Hwa
    • Korean Journal of Agricultural Science
    • /
    • v.38 no.2
    • /
    • pp.315-324
    • /
    • 2011
  • Riparian vegetation distribution patterns and diversity relative to various fluvial geomorphic channel patterns, stream bank stabilization methods, and stream flow processes are described and interpreted for selected nature-friendly small stream bank protection of Goesan, central Korea. Idong Stream Pilot Project, which began in May 2003 and finished in December 2003, was selected to develop effective methods which was nature-friendly stream bank protection. The project aim to maintain or increase stream bank stabilization ecosystem goods and services while protecting downstream and stream bank ecosystem. A number of protecting methods which were a Flight of fieldstone, Vegetation block, Green river block, Stone net, Green environment block, Eco friendly cobble, Vegetation mat and Geo-green cell and Firefly block were applied on the bank of Idong stream. The stream sites have been monitored about vegetation conditions each method in 2007. We selected six points to separately investigate in left and right bank. The main purpose of this study was to find out suitable methods and to improve stream restoration techniques for ecosystem. On the stream bank, H environment block method (9.7) was the highest average of vegetation coverage and Firefly block method (3.87) was the lowest average in applied methods.

Intelligent Digital Redesign of Uncertain Nonlinear Systems : Global approach (불확실성이 포함된 비선형 시스템에 대한 전역적 접근의 지능형 디지털 재설계)

  • Sung Hwachang;Joo Younghoon;Park Jinbae;kim Dowan
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2005.11a
    • /
    • pp.95-98
    • /
    • 2005
  • This paper presents intelligent digital redesign method of global approach for hybrid state space fuzzy-model-based controllers. For effectiveness and stabilization of continuous-time uncertain nonlinear systems under discrete-time controller, Takagi-Sugeno(TS) fuzzy model is used to represent the complex system. And global approach design problems viewed as a convex optimization problem that we minimize the error of the norm bounds between nonlinearly interpolated linear operators to be matched. Also by using the power series, we analyzed nonlinear system's uncertain parts more precisely. When a sampling period is sufficiently small, the conversion of a continuous-time structured uncertain nonlinear system to an equivalent discrete -time system have proper reason. Sufficiently conditions for the global state -matching of the digitally controlled system are formulated in terms of linear matrix inequalities (LMls). Finally, we prove the effectiveness and stabilization of the proposed intelligent digital redesign method by applying the chaotic Lorentz system.

  • PDF

Numerical Study on the Stabilization of Turbulent Swirling Lifted Premixed Syngas Flames (석탄가스 난류선회유동 예혼합부상화염의 안정성 해석)

  • Kang, Sung-Mo;Lee, Jeong-Won;Kim, Yong-Mo
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2008.05a
    • /
    • pp.349-352
    • /
    • 2008
  • This study has numerically modeled the combustion processes of the turbulent swirling premixed lifted syngas flames in the low-swirl burner (LSB). In these turbulent swirling premixed flames, the four tangentially-injected air jets induce the turbulent swirling flow which plays the crucial role of stabilizing the turbulent lifted flames. In the present approach, the turbulence-chemistry interaction is represented by the level-set based flamelet model. Numerical results indicate clearly that the present level-set based flamelet approach has realistically simulated the structure and stabilization mechanism of the turbulent swirling premixed lifted flames in the low-swirl burner. Computations are made for the wide range of the syngas chemical composition and the dilution level at two pressure conditions (1.0, 5.0 bar). Numerical results indicate that the lifted height in the LSB is increased by decreasing the H2 percentage and increasing the dilution level at the given equivalence ratio. It is also found that the flashback is occurred for the hydrogen composition higher than 80% at the equivalence ratio, 0.8. However, at the syngas composition range in the IGCC system, the stable lean-premixed lifted flames are formed at the low-swirl burner.

  • PDF

Recycling of Wastepaper(12) -Froth-Flotation Conditions for Enhancement of Fines Fractionation Selectivity and Efficiency- (고지재생연구(제12보) -부상부유 처리의 미세분 분급 선택성과 효율 상승을 위한 처리조건-)

  • 여성국;류정용;신종호;송봉근;서영범
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.33 no.1
    • /
    • pp.16-23
    • /
    • 2001
  • Hydraulic transport of fines up to the surface of flotation cell was supposed to be a mechanism of fines fractionation through the froth-flotation. Efficient fractionation of fines means efficient skimming out of flotation rejects as much as possible with least long fiber loss. The selectivity of fines fractionation was found to be mainly affected by long fibers flocculation degree in this study. Lack of sufficient flocculation of long fibers could lead to extensive loss of long fibers. It was also found that higher flotation flux caused higher flotation reject as well as the increase of long fiber loss, but did not affect the fine content ratio in the flotation reject. We controlled the flotation flux and the stock consistency, and chose a cationic polymer to maximize the flocculation of long fibers and to increase the amount of flotation reject. The highest efficiency of fines fractionation was obtained at 1.3% of stock consistency and at 100L/min of flotation flux in our experimental set up. The cationaic polymer we chose was found to be very effective in fiber flocculation and flotation froth stabilization. New definitions of fractionation efficiency were introduced in this study to compare the results more clearly.

  • PDF