The data used in this work was provided by the Ecosac fish farm. The authors wish to express their appreciation for this and for all the support throughout the investigation, especially to the production engineer Grover Cedillo. This research has received financial support from the government of Peru, under contract 49-2018 of the project Proyecto de Mejoramiento y Ampliacion de los Servicios del Sistema Nacional de Ciencia, Tecnologia e Innovacion Tecnologica 8682PE, of the CON-CYTEC/FONDECYT/World Bank Group.

Memory charts like EWMA-S(2)or CUSUM-S(2)are designed to detect a particular change in the process variance efficiently. However, the charts could be inefficient to detect some other shifts. To overcome this constraint, control charts with adaptive schemes that are efficient for a wide range of shifts can be used. This work proposes new adaptive EWMA charts for the dispersion (AEWMA-S-2) based on an adaptive smoothing parameter that relates its value to the potential shift of the process. A Markov chain approach is used to optimize its design. A simulation experiment shows the advantage of the proposed charts.

Early embryonic development is driven exclusively by maternal gene products deposited into the oocyte. Although critical in establishing early developmental programs, maternal gene functions have remained elusive due to a paucity of techniques for their systematic disruption and assessment. CRISPR-Cas13 systems have recently been employed to degrade RNA in yeast, plants, and mammalian cell lines. However, no systematic study of the potential of Cas13 has been carried out in an animal system. Here, we show that CRISPR-RfxCas13d (CasRx) is an effective and precise system to deplete specific mRNA transcripts in zebrafish embryos. We demonstrate that zygotically expressed and maternally provided transcripts are efficiently targeted, resulting in a 76% average decrease in transcript levels and recapitulation of well-known embryonic phenotypes. Moreover, we show that this system can be used in...