• 제목/요약/키워드: Population parameters

검색결과 850건 처리시간 0.031초

암환자에게 반코마이신의 집단약물동태학 모델연구 (Population Pharmacokinetic Modeling of Vancomycin in Patients with Cancer)

  • 최준식;민영돈;범진필
    • 약학회지
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    • 제43권2호
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    • pp.160-168
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    • 1999
  • The purpose of this study was to determine pharmacokinetic parameters of vancomycin using peak and trough plasma level (PTL) and Bayesian analysis in 20 Korean normal volunteers, 16 gastric cancer and 12 lymphoma patients and also using the compartment model dependent (nonlinear least squares regression: NLSR) and compartment model independent (Lagrange) analysis in 10 ovarian cancer patients. Nonparametric expected maximum (NPEM) algorithm for calculation of the population pharmacokinetic parameters was used, and these parameters were applied for clinical pharmacokinetic parameters by Bayesian analysis. Vancomycin was administered as dose of 1.0 g every 12 hrs for 3 days by IV infusion over 60 minutes in normal volunteers, gastric cancer and lymphoma patients. Population pharmacokinetic parameters, K and Vd in gastric cancer and lymphoma patients using NPEM algorithm were $0.158{\pm}0.014{\;}hr^{-1},{\;}0.630{\pm}0.043{\;}L/kg{\;}and{\;}0.131{\pm}0.0261{\;}hr^{-1},{\;}0.631{\pm}0.089{\;}L/kg$ respectively. The K and Vd in gastric cancer and lymphoma patients using Bayesian analysis were $0.151{\pm}0.027,{\;}0.126{\pm}0.056{\;}hr^{-1}{\;}and{\;}0.62{\pm}0.105,{\;}0.63{\pm}0.095{\;}L/kg$. The K and Vd in ovarian cancer patient using the NLSR and Lagrange analysis were $0.109{\pm}0.008,{\;}0.126{\pm}0.012{\;}hr^{-1}{\;}and{\;} 0.76{\pm}0.08,{\;}0.69{\pm}0.19{\;}L/kg$, respectively. It is necessary for effective dosage regimen of vancomycin in cancer patients to use these population parameters.

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An Overview of Bootstrapping Method Applicable to Survey Researches in Rehabilitation Science

  • Choi, Bong-sam
    • 한국전문물리치료학회지
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    • 제23권2호
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    • pp.93-99
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    • 2016
  • Background: Parametric statistical procedures are typically conducted under the condition in which a sample distribution is statistically identical with its population. In reality, investigators use inferential statistics to estimate parameters based on the sample drawn because population distributions are unknown. The uncertainty of limited data from the sample such as lack of sample size may be a challenge in most rehabilitation studies. Objects: The purpose of this study is to review the bootstrapping method to overcome shortcomings of limited sample size in rehabilitation studies. Methods: Articles were reviewed. Results: Bootstrapping method is a statistical procedure that permits the iterative re-sampling with replacement from a sample when the population distribution is unknown. This statistical procedure is to enhance the representativeness of the population being studied and to determine estimates of the parameters when sample size are too limited to generalize the study outcome to target population. The bootstrapping method would overcome limitations such as type II error resulting from small sample sizes. An application on a typical data of a study represented how to deal with challenges of estimating a parameter from small sample size and enhance the uncertainty with optimal confidence intervals and levels. Conclusion: Bootstrapping method may be an effective statistical procedure reducing the standard error of population parameters under the condition requiring both acceptable confidence intervals and confidence level (i.e., p=.05).

Evaluation of Commercial Pheromones on the Population Dynamics of Spodoptera frugiperda (J. E. smith) and Mythimna loreyi (Duponchel) (Lepidoptera: Noctuidae)

  • Seo Yeon Hong;Hwi Jong Yi;Young Nam Yoon;Yun Woo Jang;Ki Do Park;Rameswor Maharjan
    • 한국작물학회지
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    • 제67권4호
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    • pp.285-295
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    • 2022
  • The trapping efficacy of five commercially available sex pheromones manufactured in Korea, the Netherlands, North America, China, and Costa Rica was evaluated to determine the population dynamics of Spodoptera frugiperda and Mythimna loreyi and their relationships with the weather parameters of maize fields in Miryang, Gyeongnam Province, Korea in 2019. The results show that the sex pheromone manufactured in Costa Rica were more efficient at capturing S. frugiperda and M. loreyi than those manufactured in other countries. The lowest number of S. frugiperda moths were captured using sex pheromones manufactured in the Netherlands. We noted that more than four population peaks of both the moth species and weather parameters influenced the moth population dynamics in Miryang. A positive relationship was observed between the population of S. frugiperda and weather parameters, such as mean temperature, rainfall, and relative humidity, for sex pheromones manufactured in Korea. Furthermore, a positive relationship was recorded between the population of M. loreyi and wind speed for the sex pheromone manufactured in Korea. The results of this study suggest that the sex pheromones manufactured in Costa Rica are the best solution for the efficient capture of S. frugiperda and M. loreyi under typical weather conditions in the southern parts of Korea. In addition, the outcomes of this study are discussed in terms of population dynamics and integrated pest management for S. frugiperda and M. loreyi as alternatives to chemical management by maize producers. Further studies related to the continuous improvement in the capture efficiency of both moth species using sex pheromones are now needed.

Estimation of Population Growth Rate using Jolly-Seber Method and Robust Design

  • Kim, Jihye;Hong, Taekyong;Choi, JinSik;Namkung, Pyong
    • Communications for Statistical Applications and Methods
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    • 제10권3호
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    • pp.919-930
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    • 2003
  • Mark-Recapture method for open population commonly use Jolly-Seber method. This method assumes that all animals are equally likely to be caught in each sample (the equal catchability). This objects are making introduction of Mark-Recapture method for open population and using the robust design that combine a open population method with close population method to solve upper problems. Then population growth rate estimators that are derived Pollock's Jolly-Seber parameters and Kendall's Jolly-Seber parameters are estimated.

Spatial Heterogeneity and Long-term Changes in Bivalve Anadara broughtoni Population: Influence of River Run-off and Fishery

  • Silina, Alla V.
    • Ocean Science Journal
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    • 제41권4호
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    • pp.211-219
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    • 2006
  • A comparison was made of population of the economically important cockle Anadara (=Scapharca) broughtoni (Bivalvia, Arcidae) inhabiting different areas of the Razdolnaya River estuary at the head of Amurskii Bay (Peter the Great Gulf, East Sea). Also, changes in cockle population density and structure, as well as in cockle growth rates during the last 20 years were studied. In all years of investigation, the morphometrical parameters and growth rates of cockles were smaller at the sites located close to the River mouth than farther down-estuary. The differences can be attributed to higher concentration of suspended particulate matter, decreased salinity and water temperature, as well as a longer exposure to these unfavorable environmental factors at sites located close to the River mouth, compared to farther sites. For two decades, cockle population density had decreased by almost 30 times at some sites in the River estuary. The main reason for this population decline is commercial over-fishing of the cockle. Besides, for the last 20 years, linear parameters of the cockles in the population decreased approximately by 30% and weight parameters, almost two times. Cockle growth rates also decreased for this period. Evidently, these facts are due to the damaging effect of dredging.

순서를 갖는 척도모수들의 사전정보 하에 k-모집단 와이블분포의 베이지안 모수추정 (Bayesian Estimation of k-Population Weibull Distribution Under Ordered Scale Parameters)

  • 손영숙;김성욱
    • 응용통계연구
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    • 제16권2호
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    • pp.273-282
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    • 2003
  • 순서화된 척도모수들의 사전정보를 가지는 k-모집단 와이블분포의 모수추정을 위한 베이지안방법이 제시된다. 모수추정은 깁스샘플링에 의해서 이루어지며, 특히 깁스샘플러에서 형태모수의 조건부 사후분포는 로그-오목함수이므로 적응기각표집(Adaptive Rejection Sampling: ARS)방법에 의해 모수생성을 하였다. 논의된 모수추정법을 전기 절연유체 고장시간자료에 적용하여 척도모수의 순서화정보를 반영한 경우와 그렇지 않은 경우를 비교하였다.

신체활동과 골초음파지표와의 연관성 (Association Between Physical Activity and Quantitative Ultrasound in a Rural Population)

  • 김승준;신민호;권순석
    • 한국전문물리치료학회지
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    • 제12권2호
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    • pp.20-27
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    • 2005
  • Osteoporosis is characterized by low bone mass and the microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture. It has been suggested that speed of sound (SOS) and broadband ultrasound attenuation (BUA) of quantitative ultrasound sonography (QUS) may provide information about not only bone density but also the microarchitecture and elastic properties of bone. Physical inactivity reduced mechanical usage and it made process to the bone changes. This study aimed to association between the physical activity and the QUS parameters in 1305 (593 men, 712 women) aged 20 years over in a rural population. Two QUS parameters, BUA (p=.23) and SOS(p=.73) were measured at the right calcaneus of postmenopausal women, no significant associations were observed between sports index and SOS and BUA. These results suggest that work, non-sports leisure physical activity (p<.01) have a significant influence on QUS parameters in a rural population. Physical activity are meaningful predictor of QUS parameters of the calcaneus in a rural population.

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지리정보시스템을 활용한 서울시 유해대기오염물질 우선순위 측정지역 선정 (Selection of Priority Monitoring Areas for Hazardous Air Pollutants (HAPs) in Seoul using Geographic Information System)

  • 김성준;박현진;이상진;김창혁;이승복;최성득
    • 한국대기환경학회지
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    • 제34권2호
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    • pp.223-232
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    • 2018
  • As the Seoul metropolitan city has the largest numbers of population and vehicles, the citizens can be exposed to hazardous air pollutants(HAPs) mainly from the vehicular exhaust and human activities. In this study, we proposed a systematic method for the selection of priority monitoring areas for HAPs using Geographic Information System (GIS). First, emission parameters(emission data, vehicle registration, monitoring data, and so on) and population parameters (population and population density) were plotted using the inverse distance weighted (IDW) interpolation. Then, the interpolation data for individual parameters, which were normalized between 1 and 5 points, were compiled for 270 grids with a resolution of $2km{\times}2km$. The total score of each grid was calculated using weights(1~5) for the individual parameters. The final ranking of each grid was assigned by four scenarios with varying fractions of the emission and population parameters from 50 : 50 to 80 : 20. Consequently, nine grids were suggested as priority monitoring areas, and all of them are located in the southwestern part of Seoul.

Bayesian estimation for finite population proportions in multinomial data

  • Kwak, Sang-Gyu;Kim, Dal-Ho
    • Journal of the Korean Data and Information Science Society
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    • 제23권3호
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    • pp.587-593
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    • 2012
  • We study Bayesian estimates for finite population proportions in multinomial problems. To do this, we consider a three-stage hierarchical Bayesian model. For prior, we use Dirichlet density to model each cell probability in each cluster. Our method does not require complicated computation such as Metropolis-Hastings algorithm to draw samples from each density of parameters. We draw samples using Gibbs sampler with grid method. We apply this algorithm to a couple of simulation data under three scenarios and we estimate the finite population proportions using two kinds of approaches We compare results with the point estimates of finite population proportions and their standard deviations. Finally, we check the consistency of computation using differen samples drawn from distinct iterates.

洛東江 下流城 濫藻 Anabaena의 個體群 變動 및 毒性 硏究 (Population Dynamics and the Toxin of Anabaena in the Lower Naktong River)

  • Choi, Ae-Ran;Park, Jin-Hong;Lee, Jin-Ae
    • ALGAE
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    • 제17권2호
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    • pp.95-104
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    • 2002
  • Population dynamics of Anabaena and the anatoxin-a concentration were monitored with physicochemical parameters at 3 sites in the lower Naktong River from May to September in 2000. Total 4 species of Anabaena (A. flosaquae, A. smithii, A. ucrainica and A. mucosa) were identified with morphological characterisitcs. Anabaena flos-aquae was most abundant among the populations. The standing crop of Anabaena ranged from 10 to 11,220 cells · $ml^{-1}$ and biomass of Anabaena more 1,000 cells · $ml^{-1}$ was obseved once at St. Mulgeum and St. Seonam, twice at St. Hagueon out of total 9 samplings. There were not significant correlations between the standing crop of Anabaena and other physicochemical parameters such as temperature, nitrate, total nitrogen, phosphate, total phophorus and N/P ratios. The frequency of trichomes with akinetes was low and ranged from 0 to 4% in the total Anabaena population and A. smithii showed highest frequency of 2.8% among all species. The population at St. Seonam showed highest frequency of 1.4% among all sampling sties. The population in September showed the highest frequency of 3.0% among all sampling period. The frequency of trichomes with heterocysts was low and ranged from 1 to 87% inthe total Anabaena population and A. smithii showed highest frequency of 55.1% among all species. The population at St. Mulgeum showed highest frequency of 17.6% among all sampling sites. The population in August showed the highest frequency of 21.4% among all sampling period. The frequency of trichomes with akinetes and/or heterocysts was not related to all the physicochemical parameters of temperature, nitrate, total nitrogen, phosphate, total phosphorus and N/P ratios. The anatoxin-a concentations were determined in algal materials dominated by Microcystis and Anabaena from June though August by derivatization using 7-fluoro-4-nitro-2, 1,3-benzoxadiazole (NBD-F) and HPLC analysis with fluorimetric detection. All the concentrations were below the detection limit of 0.1 ㎍ · $l^{-1}$ in the present study.