Bootstrap methods are considered in the application of statistical process control because they can deal with unknown distributions and are easy to calculate using a personal computer. In this study we propose the use...Bootstrap methods are considered in the application of statistical process control because they can deal with unknown distributions and are easy to calculate using a personal computer. In this study we propose the use of bootstrap-t multivariate control technique on the minimax control chart. The technique takes care of correlated variables as well as the requirement of the distributional assumptions needed for the operation of the minimax control chart. The bootstrap-t technique provides the mean θB of all the bootstrap estimators ** where θi is the estimate using the ith bootstrap sample and B is the number of bootstraps. The computation of the proposed bootstrap-t minimax statistic was performed on the values obtained from the bootstrap estimation. This method was used to determine the position of the four control limits of the minimax control chart. The bootstrap-t approach introduced to minimax multivariate control chart helps to detect shifts in the mean vector of a multivariate process and it overcomes the computational complexity of obtaining the distribution of multivariate data.展开更多
BACKGROUND Epigenetic disruptions have been implicated in some cases of infertility and can serve as therapeutic targets.However,the involvement of epigenetics in infertility has not received adequate attention.AIM Th...BACKGROUND Epigenetic disruptions have been implicated in some cases of infertility and can serve as therapeutic targets.However,the involvement of epigenetics in infertility has not received adequate attention.AIM This study aimed to determine the epigenetic basis of infertility in order to enhance public knowledge.METHODS Relevant articles on the subject were collected from PubMed,RCA,Google Scholar,SpringerLink,and Scopus.The articles were pooled together and duplicates were removed using Endnote software.RESULTS Available information shows that epigenetic mechanisms,mainly DNA methylation,histone modification,and microRNA interference are necessary for normal gametogenesis and embryogenesis.As a result,epigenetic disruptions in genes that control gametogenesis and embryogenesis,such as DDX3X,ADH4,AZF,PLAG1,D1RAS3,CYGB,MEST,JMJD1A,KCNQ1,IGF2,H19,and MTHFR may result in infertility.Aberrant DNA methylation during genomic imprinting and parental epigenetic mark erasures,in particular,may affect the DNA epigenomes of sperm and oocytes,resulting in reproductive abnormalities.in the sperm may also cause reproductive abnormalities.Furthermore,overexpression or repression of certain microRNAs embedded in the ovary,testis,embryo,as well as granulosa cells and oocytes may impair reproduction.Male infertility is characterized by spermatogenesis failure,which includes oligozoospermia,asthenozoospermia,and teratozoospermia,while female infertility is characterized by polycystic ovary syndrome.Some epigenetic modifications can be reversed by deactivating the regulatory enzymes,implying that epigenetic reprogramming could help treat infertility in some cases.For some disorders,epigenetic drugs are available,but none have been formulated for infertility.CONCLUSION Some cases of infertility have an epigenetic etiology and can be treated by reversing the same epigenetic mechanism that caused it.As a result,medical practitioners are urged to come up with epigenetic treatments for infertility that have an epigenetic cause.展开更多
文摘Bootstrap methods are considered in the application of statistical process control because they can deal with unknown distributions and are easy to calculate using a personal computer. In this study we propose the use of bootstrap-t multivariate control technique on the minimax control chart. The technique takes care of correlated variables as well as the requirement of the distributional assumptions needed for the operation of the minimax control chart. The bootstrap-t technique provides the mean θB of all the bootstrap estimators ** where θi is the estimate using the ith bootstrap sample and B is the number of bootstraps. The computation of the proposed bootstrap-t minimax statistic was performed on the values obtained from the bootstrap estimation. This method was used to determine the position of the four control limits of the minimax control chart. The bootstrap-t approach introduced to minimax multivariate control chart helps to detect shifts in the mean vector of a multivariate process and it overcomes the computational complexity of obtaining the distribution of multivariate data.
文摘BACKGROUND Epigenetic disruptions have been implicated in some cases of infertility and can serve as therapeutic targets.However,the involvement of epigenetics in infertility has not received adequate attention.AIM This study aimed to determine the epigenetic basis of infertility in order to enhance public knowledge.METHODS Relevant articles on the subject were collected from PubMed,RCA,Google Scholar,SpringerLink,and Scopus.The articles were pooled together and duplicates were removed using Endnote software.RESULTS Available information shows that epigenetic mechanisms,mainly DNA methylation,histone modification,and microRNA interference are necessary for normal gametogenesis and embryogenesis.As a result,epigenetic disruptions in genes that control gametogenesis and embryogenesis,such as DDX3X,ADH4,AZF,PLAG1,D1RAS3,CYGB,MEST,JMJD1A,KCNQ1,IGF2,H19,and MTHFR may result in infertility.Aberrant DNA methylation during genomic imprinting and parental epigenetic mark erasures,in particular,may affect the DNA epigenomes of sperm and oocytes,resulting in reproductive abnormalities.in the sperm may also cause reproductive abnormalities.Furthermore,overexpression or repression of certain microRNAs embedded in the ovary,testis,embryo,as well as granulosa cells and oocytes may impair reproduction.Male infertility is characterized by spermatogenesis failure,which includes oligozoospermia,asthenozoospermia,and teratozoospermia,while female infertility is characterized by polycystic ovary syndrome.Some epigenetic modifications can be reversed by deactivating the regulatory enzymes,implying that epigenetic reprogramming could help treat infertility in some cases.For some disorders,epigenetic drugs are available,but none have been formulated for infertility.CONCLUSION Some cases of infertility have an epigenetic etiology and can be treated by reversing the same epigenetic mechanism that caused it.As a result,medical practitioners are urged to come up with epigenetic treatments for infertility that have an epigenetic cause.
