1.WOMBAT: a tool for mixed model analyses in quantitative genetics by restricted maximum likelihood (REML).
Journal of Zhejiang University. Science. B 2007;8(11):815-821
WOMBAT is a software package for quantitative genetic analyses of continuous traits, fitting a linear, mixed model; estimates of covariance components and the resulting genetic parameters are obtained by restricted maximum likelihood. A wide range of models, comprising numerous traits, multiple fixed and random effects, selected genetic covariance structures, random regression models and reduced rank estimation are accommodated. WOMBAT employs up-to-date numerical and computational methods. Together with the use of efficient compilers, this generates fast executable programs, suitable for large scale analyses. Use of WOMBAT is illustrated for a bivariate analysis. The package consists of the executable program, available for LINUX and WINDOWS environments, manual and a set of worked example, and can be downloaded free of charge from (http://agbu. une.edu.au/~kmeyer/wombat.html).
Animals
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Likelihood Functions
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Mice
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Models, Genetic
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Software
2.Analysis and Discussion on Calculating Likelihood Ratio of DNA Mixture.
Ying LIU ; He REN ; Lin-lin GAO ; Yan SHI ; Chong CHEN ; Ya-cheng LIU
Journal of Forensic Medicine 2015;31(6):441-444
OBJECTIVE:
To analyze and discuss four methods of calculating likelihood ratio of DNA mixture.
METHODS:
In the case with CNAS-T0757 proficiency testing in 2013, the likelihood ratios were calculated and compared among four methods, including unrestricted combinatorial method, Clayton's method, p2 principle method, and recommendations from ISFG.
RESULTS:
The likelihood ratios were maximum by Clayton's method and recommendations from ISFO, followed by result of the unrestricted combinational method. The minimum likelihood ratio was obtained by p2 principle.
CONCLUSION
The unrestricted combinational method could give fUrthest consideration to both information preservation and appraiser protection.
DNA/genetics*
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DNA Fingerprinting
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Humans
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Likelihood Functions
3.The Learning Curve for Laparoscopic Totally Extraperitoneal Herniorrhaphy by Logarithmic Function.
Oh Chul KWON ; Yong Hae BAIK ; Min Gu OH ; Yeong Jin PARK ; Beom Seok KWAK ; In Woong HAN
Journal of Minimally Invasive Surgery 2016;19(4):126-129
PURPOSE: Totally extraperitoneal (TEP) hernia repair has gained in popularity in the past two decades. Despite the advantages TEP hernia repair, the approach is hindered by the relatively long learning curve of the surgery. We tried to estimate the necessary number of repetitions of TEP hernia repair in the learning curve using logarithmic and exponential function models. METHODS: We performed a retrospective review of all patients who underwent TEP hernia repair by a single surgeon consecutively at a single center. We calculated how many operations were needed to achieve a reduction in the expected operating time to mean operating time using logarithmic and exponential function models. RESULTS: In the 91 patients, the logarithmic function model predicted that 37 cases were needed to overcome the learning curve for TEP hernia repair while the exponential model predicted that 39 cases were needed. CONCLUSION: According to this study, at least 37 to 39 cases are needed in the overcome learning curve of TEP hernia repair. Further studies are needed to optimize surgical education and maximize quality.
Education
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Herniorrhaphy*
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Humans
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Learning Curve*
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Learning*
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Likelihood Functions
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Retrospective Studies
4.Reconstruction of dynamic positron emission tomographic images by exploiting low rank and sparse penalty.
Xia-Ping WEI ; ; Xue-Wen JIANG ; Xiao-Mian MA ; Li-Jun LU
Journal of Southern Medical University 2015;35(10):1446-1450
OBJECTIVETo propose a new method for dynamic positron emission tomographic (PET) image reconstruction using low rank and sparse penalty (L&S).
METHODSThe L&S reconstruction model was established and the split Bregman method was used to solve the optimal cost function. The one-tissue compartment model was used to simulate a set of PET 82Rb myocardial perfusion image. The L&S reconstruction method was compared with maximum likelihood expectation maximization (MLEM) method, low-rank penalty method and sparse penalty method.
RESULTSThe L&S reconstruction method had the smallest MSE and well maintained the feature information. The polar map created by L&S method was the most similar with the reference actual polar map.
CONCLUSIONL&S reconstruction method is better than the other three methods in both visual and quantitative analysis of the PET images.
Algorithms ; Humans ; Likelihood Functions ; Positron-Emission Tomography ; methods
5.Recent advances in Bayesian inference of isolation-with-migration models
Genomics & Informatics 2019;17(4):37-
Isolation-with-migration (IM) models have become popular for explaining population divergence in the presence of migrations. Bayesian methods are commonly used to estimate IM models, but they are limited to small data analysis or simple model inference. Recently three methods, IMa3, MIST, and AIM, resolved these limitations. Here, we describe the major problems addressed by these three software and compare differences among their inference methods, despite their use of the same standard likelihood function.
Bayes Theorem
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Gene Flow
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Likelihood Functions
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Phylogeny
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Statistics as Topic
6.Application of statistical distribution of PM10 concentration in air quality management in 5 representative cities of China.
Xi WANG ; Ren Jie CHEN ; Bing Heng CHEN ; Hai Dong KAN
Biomedical and Environmental Sciences 2013;26(8):638-646
OBJECTIVETo estimate the frequency of daily average PM10 concentrations exceeding the air quality standard (AQS) and the reduction of particulate matter emission to meet the AQS from the statistical properties (probability density functions) of air pollutant concentration.
METHODSThe daily PM10 average concentration in Beijing, Shanghai, Guangzhou, Wuhan, and Xi'an was measured from 1 January 2004 to 31 December 2008. The PM10 concentration distribution was simulated by using the lognormal, Weibull and Gamma distributions and the best statistical distribution of PM10 concentration in the 5 cities was detected using to the maximum likelihood method.
RESULTSThe daily PM10 average concentration in the 5 cities was fitted using the lognormal distribution. The exceeding duration was predicted, and the estimated PM10 emission source reductions in the 5 cities need to be 56.58%, 93.40%, 80.17%, 82.40%, and 79.80%, respectively to meet the AQS.
CONCLUSIONAir pollutant concentration can be predicted by using the PM10 concentration distribution, which can be further applied in air quality management and related policy making.
Air Pollutants ; analysis ; China ; Cities ; Environmental Monitoring ; Likelihood Functions ; Particulate Matter ; analysis
7.Advances in independent component analysis and its application.
Journal of Biomedical Engineering 2003;20(2):366-374
The independent component analysis (ICA) is a new technique in statistical signal processing, which decomposes mixed signals into statistical independent components. The reported applications in biomedical and radar signal have demonstrated its good prospect in various blind signal separation. In this paper, the progress of ICA in such as its principle, algorithm and application and advance direction of ICA in future is reviewed. The aim is to promote the research in theory and application in the future.
Algorithms
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Brain
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physiology
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Humans
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Likelihood Functions
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Magnetic Resonance Imaging
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Nonlinear Dynamics
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Signal Processing, Computer-Assisted
8.Accuracy of correlation function method for evaluating pulsed high intensity focused ultrasound.
Xin ZHAO ; Jianzhong ZOU ; Feng WU ; Fang LIU ; Jiao JIAO
Journal of Southern Medical University 2013;33(1):40-43
OBJECTIVETo investigate the accuracy of ultrasound monitoring during pulsed high intensity focused ultrasound (PHIFU) treatment and improve the sensitivity of ultrasound monitoring of tissue necrosis caused by PHIFU treatment.
METHODSBovine liver ex vivo was dot-exposed with HIFU at the therapeutic doses of 2000 J (group A) and 1440 J (group B). The two groups were further divided into groups A1 (power 100 W, duty cycle 100%, irradiate 20 s) A2 (power 100 W, duty cycle 50%, irradiate 40 s), A3 (power 100 W, duty cycle 40%, irradiate 50 s), B1 (power 120 W, duty cycle 100%, irradiate 12 s), B2 (power 100 W, duty cycle 50%, irradiate 24 s), and B3 (power 100 W, duty cycle 40%, irradiate 30 s). The gray scale changes in the ultrasonic images after the exposures were observed, and the correlation function of the image was calculated before and after the exposure. The accuracy of evaluations based on the correlation function and gray-scale changes was compared.
RESULTSThe correct rate of gray scale-based evaluation of tissue necrosis caused by PHIFU was only 51%, while that by correlation function-based evaluation reached 85%.
CONCLUSIONMonitoring of tissue necrosis caused by PHIFU treatment can not rely solely on evaluation of gray-scale change of the ultrasound images, and the correlation function-based evaluation can be more accurate and sensitive for that purpose.
Animals ; Cattle ; High-Intensity Focused Ultrasound Ablation ; methods ; In Vitro Techniques ; Likelihood Functions ; Liver ; diagnostic imaging ; Ultrasonography
9.Long-term trend of colorectal cancer survival rate in Qidong, 1972-2016.
Ming Bo JIANG ; Yong Sheng CHEN ; Jun WANG ; Yuan You XU ; Lu Lu DING ; Yong Hui ZHANG ; Jian Guo CHEN ; Jian ZHU
Chinese Journal of Oncology 2022;44(12):1357-1361
Objective: The survival of colorectal cancer in Qidong City, Jiangsu Province from 1972 to 2016 was analyzed to provide a basis for the evaluation of prognosis and the formulation of prevention and control measures. Methods: Colorectal cancer data were obtained from the Qidong Cancer Registration and Reporting System, and the follow-up was up to December 31, 2021. The observed survival rate (OSR) and relative survival rate (RSR) were calculated by SURV 3.01 software, and the trend test was performed by Hakulinen's likelihood ratio test. The Joinpoint regression model was used to calculate the average annual percentage change (AAPC) of survival, and the ARIMA model was used to predict the trend of colorectal cancer survival. Results: There were 8 637 new cases of colorectal cancer in Qidong from 1972 to 2016. Dividing 1972-2016 into 9 periods at 5-year intervals, the 5-year OSR from 1972-1976 to 2012-2016 increased from 21.86% to 48.86%, and the 5-year RSR increased from 26.45% to 59.91%. The increasing trend of RSR was statistically significant (χ(2)=587.47, P<0.001). From 1972 to 2016, the survival rates of colorectal cancer in different sexes in Qidong were similar, and the 5-year RSR was 44.63% for men and 44.07% for women. Since the 1990s, the 5-year OSR and RSR for men have been lower than those for women. From 1972 to 2016, the 5-year RSR of colorectal cancer in Qidong was significantly improved in the 65-74 and ≥75-year-old groups, but the survival rate of the ≥75-year-old group was still the lowest (36.78%), followed by the 35-44-year-old group ( 43.04%). The time trend showed that the overall AAPC of colorectal cancer 5-year RSR in Qidong from 1972 to 2016 was 2.50% (t=16.45, P<0.001). The upward trend of different sexes was consistent, and the increase was greater in women (AAPC for males=2.18%, AAPC for females=2.54%, both P<0.05). The 5-year RSR of colorectal cancer in each age group showed an upward trend, and the AAPCs of the 35-44, 45-54, 55-64, 65-74, and ≥75-year-old groups were 1.54%, 1.83%, 2.00%, 3.51% and 4.35%, respectively (all P<0.05). The prediction results of colorectal cancer survival rate showed that the 5-year RSR of colorectal cancer in Qidong will increase to 71.62% by 2026. Conclusions: The overall survival rate of colorectal cancer patients in Qidong has been greatly improved, but there is still room for improvement. We should continue to pay attention to the early diagnosis and early treatment of colorectal cancer.
Male
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Humans
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Female
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Aged
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Adult
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Survival Rate
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Prognosis
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Software
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Likelihood Functions
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Colorectal Neoplasms
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China/epidemiology*
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Incidence
10.Calculation of Likelihood Ratio for Identifying Half Sibling Relationship When Both Biological Mothers Participate.
Xue Ling OU ; Hui Ling LU ; Jian SHEN ; Ning QU ; Hao LIANG
Journal of Forensic Medicine 2019;35(6):662-666
Objective To derive the formulae for likelihood ratio (LR) calculation of half sibling relationships when both mothers participate. Methods Based on the fact that both biological mothers participate in the identification of half sibling relationship between the two individuals, test hypothesis for the identification of half sibling relationship was established. Conditional probability ratios of genetic evidence under null hypothesis and alternative hypothesis conditions were simplified, and then applied to a real case of half sibling relationship identification. At the same time, the LR of half sibling relationships under the assumption that only a single biological mother or none of the biological mothers participate were respectively calculated. Results In the cases of identification of half sibling relationship from same fathers, with no biological father involved, after the same genetic indicator test analysis, when both biological mothers participate in the identification, the accumulated LR value was higher than that of accumulated LR with only a single biological mother or no parents participating. Conclusion When the autosome STR test is used for the identification and analysis of half sibling relationship between two individuals, the calculation of LR is more simple, intuitive and operable with both mothers participating. The biological mothers should participate in the test as much as possible, otherwise the number of STR loci would need to be increased for a more specific conclusion.
Alleles
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Female
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Forensic Genetics
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Genotype
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Humans
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Likelihood Functions
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Models, Genetic
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Mothers
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Population Groups
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Siblings