• Title/Summary/Keyword: Kinetic Parameters

Search Result 969, Processing Time 0.027 seconds

Pharmacokinetics of a New PEG-hemoglobin SBI for Single Intravenous Administration to Rats (흰쥐에 있어서 PEG-헤모글로빈 SBI의 단회정맥투여 약물동태)

  • 신호철;심희옥;유승룡;김종춘;양승돈;정문구
    • YAKHAK HOEJI
    • /
    • v.44 no.3
    • /
    • pp.232-236
    • /
    • 2000
  • An intravenous pharmacokinetics for a new red cell substitute, PEG-hemoglobin SB1, was studied in SD rats. Total-hemoglobin and its metabolite methemoglobin in the plasma were determined using a spectrophotometer. The limit of quantitation was 0.01g/dL and the C.V for interday assay reproducibility was less than 6%. Upon intravenous administration of anticipated clinical dose, 10 ml(0.7 gHb)/kg, plasma concentration curve of total-hemoglobin was well described by one-compartment model. The $t_{\frac{1}{2}},{\;}CL_{t}$, Vd and $AUC^{0-48hr}$ were $8.23{\pm}0.96{\;}hr,{\;}0.06{\;}{\pm}{\;}0.01 {\;}dL/hr/kg,{\;}0.66{\pm}0.05{\;}dL/lg{\;}and{\;}13.6{\;}{\pm}{\;}1.01g{\cdot}hr/dL$, respectively, in male rats(n=5, $mean{\;}{\pm}{\;}SD$). Those parameters in female rats were $9.21{\;}\pm{\;}2.31{\;}hr,{\;}0.06{\;}{\pm}{\;}0.01{\;}dL/hr/kg,{\;}0.79{\pm}{\;}0.08{\;}dL/kg{\;}and{\;}13.0{\;}{\pm}{\;}2.36{\;}g{\cdot}hr/dL$, respectively. Similar kinetic profiles between males and females were also obtained from other parameters. Small amount of methemoglobin, an oxidative metabolite of SB1, was detected in the plasma of both sexes, where the $AUC^{0-48{\;}hr,m}$ and $t_{{\frac{1}{2}},m}$ were approximately $1.5{\;}g{\cdot}hr/dL$ and 20 hr, respectively. The present work provides a critical kinetic data for the effective clinical applications of PEG-hemoglobin SB1.

  • PDF

Simulating reactive distillation of HIx (HI-H2O-I2) system in Sulphur-Iodine cycle for hydrogen production

  • Mandal, Subhasis;Jana, Amiya K.
    • Nuclear Engineering and Technology
    • /
    • v.52 no.2
    • /
    • pp.279-286
    • /
    • 2020
  • In this article, we develop a reactive distillation (RD) column configuration for the production of hydrogen. This RD column is in the HI decomposition section of the sulphur - iodine (SI) thermochemical cycle, in which HI decomposition and H2 separation take place simultaneously. The section plays a major role in high hydrogen production efficiency (that depends on reaction conversion and separation efficiency) of the SI cycle. In the column simulation, the rigorous thermodynamic phase equilibrium and reaction kinetic model are used. The tuning parameters involved in phase equilibrium model are dependent on interactive components and system temperature. For kinetic model, parameter values are adopted from the Aspen flowsheet simulator. Interestingly, there is no side reaction (e.g., solvation reaction, electrolyte decomposition and polyiodide formation) considered aiming to make the proposed model simple that leads to a challenging prediction. The process parameters are determined on the basis of optimal hydrogen production as reflux ratio = 0.87, total number of stages = 19 and feeding point at 8th stage. With this, the column operates at a reasonably low pressure (i.e., 8 bar) and produces hydrogen in the distillate with a desired composition (H2 = 9.18 mol%, H2O = 88.27 mol% and HI = 2.54 mol%). Finally, the results are compared with other model simulations. It is observed that the proposed scheme leads to consume a reasonably low energy requirement of 327 MJ/kmol of H2.

The Characteristics of Obstacle Gaits in Female Elders after 12 Weeks of an Aquatic Exercise Program (12주간의 수중 운동을 수행 한 여성노인의 장애물 보행 특성)

  • Kim, Suk-Bum;Yu, Yeon-Joo
    • Korean Journal of Applied Biomechanics
    • /
    • v.19 no.3
    • /
    • pp.539-547
    • /
    • 2009
  • The purpose of this study was to investigate the changes of kinetic and kinematic parameters in obstacle gaits after 12 weeks of an aquatic exercise program. Eight female elders walked in four different heights of obstacles(0, 2.5, 5.1, & 15.2cm) on their self-selected speed. The ROM of hip was significantly increased after the aquatic exercise program. Swing and Stance duration were decreased. The step length was significantly increased and the step width was decreased. After the exercise program the clearance between the right foot and the top of obstacle(except 15.2cm) increased and the crossing speed was increased. The braking force, propulsive force, braking impulse, and propulsive impulse were significantly changed after the aquatic exercise program. The 12 weeks of the aquatic exercise program resulted in lower body strength and balance gains in female elders. The improvements were associated with changes in kinetic and kinematic parameters leading to an obstacle-crossing speed and a safer lower-limb control. The aquatic exercise program is suggested as an effective intervention to promote gait ability and prevent fall-related to the injuries.

The Effect of Rehabilitation Training Programs on the Kinetic and Kinematic Parameters During Sit-To-Stand in Chronic Stroke Patients (만성편마비 환자의 재활 운동 유형이 일어서기 동작의 운동학 및 운동역학적 변인에 미치는 영향)

  • Yu, Yeon-Joo;Yoon, Te-Jin;Eun, Seon-Deok
    • Korean Journal of Applied Biomechanics
    • /
    • v.16 no.2
    • /
    • pp.121-134
    • /
    • 2006
  • The purpose of this study was to analyze the effect of different types of rehabilitation training program on the kinetic and kinematic parameters during sit-to-stand movement(STS) in chronic stroke patients. Two groups of hemiparetic patients, experimental and control, participated in the study. The experimental group participated in a 10-week training program (three sessions/wk, $1{\sim}1.5\;hr/session$) consisting of a warm-up, aerobic exercises, lower extremity strengthening. and a cool-down. The control group participated in an aerobic exercise. Three dimensional kinematic analysis and force platform; were used to analyze the duration of STS, lower extremity angle, and weight bearing ability. The experimental group which had more strength of lower extremity displayed decrease in duration of STS. However, the control group showed increases in duration during sit-to-stand movement. The control group flexed their trunk more than the group did Therefore, it took more time to extend their trunk during STS. The duration in sit-to-stand was affected by the strength of lower extremity and the angle of trunk movement. The angles of ankle and knee joint had an influenced on duration of STS. The post experimental group performed with their feet near the front leg of the chair during sit-to-stand, therefore the duration was decreased. The repetitive sit-to-stand movements as a resistance exercise was effective to hemiparetic patients in learning mechanism of sit-to-stand. The control group showed decreased differences in the vertical ground reaction forces between paretic and non-paretic limbs. Their training program included strengthening exercise that may help improving weight bearing ability. The control group showed increases in the center of pressure in the anteroposterior and mediolateral displacement. This means that the stability of movement was low in the control group. Their training program which combined aerobic and strengthening exercises that are more effective to improve the stability of movement.

Application of Probabilistic Model to Calculate Probabilities of Escherichia coli O157:H7 Growth on Polyethylene Cutting Board

  • Lee, Joo-Yeon;Suk, Hee-Jin;Lee, Hee-Young;Lee, Soo-Min;Yoon, Yo-Han
    • Food Science of Animal Resources
    • /
    • v.32 no.1
    • /
    • pp.62-67
    • /
    • 2012
  • This study calculated kinetic parameters of Escherichia coli O157:H7 and developed a probabilistic model to estimate growth probabilities of E. coli O157:H7 on polyethylene cutting boards as a function of temperature and time. The surfaces of polyethylene coupons ($3{\times}5$ cm) were inoculated with E. coli O157:H7 NCCP11142 at 4 Log $CFU/cm^2$. The coupons were stored at 13 to $35^{\circ}C$ for 12 h, and cell counts of E. coli O157:H7 were enumerated on McConkey II with sorbitol agar every 2 h. Kinetic parameters (maximum specific growth rate, Log $CFU/cm^2/h$; lag phase duration, h; lower asymptote, Log $CFU/cm^2$; upper asymptote, Log $CFU/cm^2$) were calculated with the modified Gompertz model. Of 56 combinations (temperature${\times}$time), the combinations that had ${\geq}$0.5 Log $CFU/cm^2$ of bacterial growth were designated with the value of 1, and the combinations that had increases of <0.5 Log $CFU/cm^2$ were given the value 0. These growth response data were fitted to the logistic regression to develop the model predicting probabilities of E. coli O157:H7 growth. Specific growth rate and growth data showed that E. coli O157:H7 cells were grown at $28-35^{\circ}C$, but there were no obvious growth of the pathogen below $25^{\circ}C$. Moreover, the developed probabilistic model showed acceptable performance to calculate growth probability of E. coli O157:H7. Therefore, the results should be useful in determining upper limits of working temperature and time, inhibiting E. coli O157:H7 growth on polyethylene cutting board.

Kinetic Investigation of Olefin Oxidation by Al(III)-Porphyrin Complexes (Al(lll)-Porphyrin착물에 의한 올레핀 산화반응 메카니즘 연구)

  • Na, Hun-Gil;Han, Man-So
    • Journal of the Korean Chemical Society
    • /
    • v.50 no.1
    • /
    • pp.46-52
    • /
    • 2006
  • studies of olefin oxidation using Al(III)-porphyrin complexes as catalyst are investigated in CH2Cl2, in which NaClO is used as terminal oxidant. Porphyrins are TPP(5,10,15,20-Tetraphenylporphyrin) and (p-X)TPP(X=CH3O, CH3, F, Cl). Olefins are styrene and (p-X)styrene (X=CH3O, CH3, Cl, Br). The values of Km and Vmax are calculated from the Michaelis-Menten equation. According to the substituents of substrate and catalyst, kinetic parameters will be measured. Investigating the correlation between the Michaelis-Menten rate parameters and the substituent constants, we were able to analyze the influence on the changes of catalytic activity or the rate determining step during the process of the formation and the dissociation of the M-oxo-olefin.

Characteristics of the Bioreactors of Hydrogen-producing Immobilized Cells (II) -Overall Effectiveness Factor in Continuous Reactors- (수소생산 고정화 생물 반응기의 특성(II) -연속 반응기에서의 총괄 효율인자 -)

  • 이명재;선용호;한정우;조영일
    • Microbiology and Biotechnology Letters
    • /
    • v.16 no.6
    • /
    • pp.510-516
    • /
    • 1988
  • The effects of input substrate concentration and dilution rate on mass transfer resistance in the operation of immobilized cell reactors were investigated using Rhodospirillum rubrum KS-301 immobilized by Ca alginate as reactor element and glucose as growth-limiting substrate. The kinetic parameters were obtained to estimate effectiveness factors. In the packed-bed reactor, internal mass transfer resistance was predominating although external resistance could not be neglected. The overall effectiveness factor was decreased with increase of dilution rate. In the continuous stirred-tank reactor, external resistance was nearly neglected and the overall effectiveness factor was not affected by dilution rate. In this experiment the overall effectiveness factors in PBR and CSTR were estimated to be 0.70 and 0.71 at D$_{i}$ = 0.2/h, R = 0.15 cm, and S$_{i}$ : 1.0g/L, respectively.

  • PDF

Evaluation of Adsorption Characteristics of 2-Picoline onto Sylopute (실로퓨트에 대한 2-피콜린의 흡착 특성 평가)

  • Yang, Ji-Won;Kim, Jin-Hyun
    • Korean Chemical Engineering Research
    • /
    • v.57 no.2
    • /
    • pp.210-218
    • /
    • 2019
  • Batch experiment studies were carried out on the adsorption of the major tar compound, 2-picoline, derived from the plant cell cultures of Taxus chinensis, using Sylopute while varying parameters such as initial 2-picoline concentration, contact time and adsorption temperature. The experimental data were fitted to the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. Comparison of results revealed that the Langmuir isotherm model could account for the adsorption isotherm data with the highest accuracy among the four isotherm models considered. From the analysis of adsorption isotherms, it was found that adsorption capacity decreased with increasing temperature and the adsorption of 2-picoline onto Sylopute was favorable. The kinetic data were well described by the pseudo-second-order kinetic model, while intraparticle diffusion and boundary layer diffusion did not play a dominated role in 2-picoline adsorption according to the intraparticle diffusion model. Thermodynamic parameters revealed the exothermic, irreversible and non-spontaneous nature of adsorption. The isosteric heat of adsorption decreased as surface loading ($q_e$) increased, indicating a heterogeneous surface.

Toe-in Gait, Associated Complications, and Available Conservative Treatments: A Systematic Review of Literature

  • Mohammad Taghi Karimi
    • Journal of Korean Foot and Ankle Society
    • /
    • v.27 no.1
    • /
    • pp.17-23
    • /
    • 2023
  • Purpose: Toe-in gait is defined as a style of walking in which the foot turns inward. It may be caused by an increase in femoral bone anteversion, tibia torsion, and metatarsus adductus. There are some conservative treatment approaches used to correct this condition. This review aimed to determine the effects of the toe-in gait on joint loading, kinematics, and kinetic parameters while walking. Moreover, it sought to determine the efficiency of various conservative treatments used to correct the condition. Materials and Methods: A literature search was conducted in the following databases: PubMed, Institute for Scientific Information (ISI), Web of Science database, EBSCO, and Embase, using the following keywords in toe, toe-in, toeing, in-toe, pigeon toe, and conservative treatment published between 1950 and 2021. The quality of the studies was evaluated using the Down and Black tool. Results: A total of 13 papers on the impact of toe-in gait on joint contact force, kinematics, kinetic parameters, and conservative approaches to management were found. The quality of the studies varied between a score of 11 and 22. The toe-in gait influences the joint contact forces and kinematics of the joints, especially the hip and pelvis. The effects of conservative treatment on the toe-in gait appear to be controversial. Conclusion: As the toe-in gait influences the joint contact force, it may increase the incidence of degenerative joint diseases. Therefore, treatment is recommended. However, there is no strong evidence on the efficacy of conservative treatments, and there are no recommendations for the use of these treatments in subjects with toe-in gait.

Kinetic Behavior of Escherichia coli on Various Cheeses under Constant and Dynamic Temperature

  • Kim, K.;Lee, H.;Gwak, E.;Yoon, Y.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.27 no.7
    • /
    • pp.1013-1018
    • /
    • 2014
  • In this study, we developed kinetic models to predict the growth of pathogenic Escherichia coli on cheeses during storage at constant and changing temperatures. A five-strain mixture of pathogenic E. coli was inoculated onto natural cheeses (Brie and Camembert) and processed cheeses (sliced Mozzarella and sliced Cheddar) at 3 to 4 log CFU/g. The inoculated cheeses were stored at 4, 10, 15, 25, and $30^{\circ}C$ for 1 to 320 h, with a different storage time being used for each temperature. Total bacteria and E. coli cells were enumerated on tryptic soy agar and MacConkey sorbitol agar, respectively. E. coli growth data were fitted to the Baranyi model to calculate the maximum specific growth rate (${\mu}_{max}$; log CFU/g/h), lag phase duration (LPD; h), lower asymptote (log CFU/g), and upper asymptote (log CFU/g). The kinetic parameters were then analyzed as a function of storage temperature, using the square root model, polynomial equation, and linear equation. A dynamic model was also developed for varying temperature. The model performance was evaluated against observed data, and the root mean square error (RMSE) was calculated. At $4^{\circ}C$, E. coli cell growth was not observed on any cheese. However, E. coli growth was observed at $10{\circ}C$ to $30^{\circ}C$C with a ${\mu}_{max}$ of 0.01 to 1.03 log CFU/g/h, depending on the cheese. The ${\mu}_{max}$ values increased as temperature increased, while LPD values decreased, and ${\mu}_{max}$ and LPD values were different among the four types of cheese. The developed models showed adequate performance (RMSE = 0.176-0.337), indicating that these models should be useful for describing the growth kinetics of E. coli on various cheeses.