BACKGROUND: Genetic skeletal abnormalities are a heterogeneous group of genetic disorders frequently presenting with disproportionate short stature. AIM OF THE STUDY: To give an idea about the frequency of genetic skeletal abnormalities, and to find out whether these disorders are really increasing in the last 16 years or not. METHODS: During the period extending from (Jan, 1st 2003-April, 1st 2007), all cases of genetic skeletal disorders referred to the Genetic Counseling Clinic, Medical City – Baghdad who were born after 1991 were included in this study as the post-war group; the pre-war group, included all cases of skeletal disorders referred prior to 1991 (Jan., 1st 1987-Jan., 1st 1990). The demographic parameters, family history of the disease plus the parental consanguinity were studied. RESULTS: The post-war group constituted 3.199% while the pre-war group constituted 2.815%. Both groups had a comparative age range. AR disorders constituted 39.75% of the post-war group and 40% in the pre-war group; AD disorders come next in both groups (37.3% vs. 33.8%) respectively. There is a noticeable increase in the occurrence of new mutations of AD disorders in the post-war group. CONCLUSION: Genetic skeletal dysplaisas are not uncommon disorders; their incidence seems to be truly increasing.
A Comparative Study of the Frequency of Occurrence of
Genetic Skeletal Disorders in Iraq before and after the Second Gulf War, 1991
Genetic Skeletal Disorders
Frequency of Occurrence
Second Gulf War
Iraq
Publication Date
Wed Apr 25 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Different Estimation Methods for System Reliability Multi-Components model: Exponentiated Weibull Distribution
Exponentiated Weibull Distribution (EWD)
Reliability of multi-component Stress – Strength models R(s
k)
Maximum likelihood estimator (MLE)
Moment estimator (MOM)
shrinkage method (Sh)
Least Squares Estimator (LS)
Rank Set Sampling (RSS). and mean squared error (MSE).
In this paper, estimation of system reliability of the multi-components in stress-strength model R(s,k) is considered, when the stress and strength are independent random variables and follows the Exponentiated Weibull Distribution (EWD) with known first shape parameter θ and, the second shape parameter α is unknown using different estimation methods. Comparisons among the proposed estimators through Monte Carlo simulation technique were made depend on mean squared error (MSE) criteria
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