= Shigeki Morita
{c}
\b[<Shigeki Morita>] is a coauthor of the 1994 isolated-heart study comparing automated <echocardiography> with a pressure-volume reference for <ventricular compliance>. The exact full name appears in the publisher byline. The experiment combined intraventricular balloon volumes, micromanometer <pressure> and image-derived short-axis <area>.<Estimation of left ventricular compliance using on-line echocardiographic automated border detection and pressure data by John Gorcsan III and others>[Publisher byline; abstract, apparatus]{ref}
The study's replication has two levels: three runs of changing volume were performed in each of six hearts. Repeated observations help describe a curve within a preparation, while different hearts supply biological replication. The reported 1,080 simultaneous measurements are not 1,080 independent hearts.<Estimation of left ventricular compliance using on-line echocardiographic automated border detection and pressure data by John Gorcsan III and others>[Abstract, three volume runs per heart and total paired observations]{ref}
An original error model shows why that distinction matters. Let $Y_{ij}=\mu+u_i+\epsilon_{ij}$, with independent heart-level effects $u_i$ of <variance> $\sigma_b^2$ and independent within-heart errors of variance $\sigma_e^2$. For $H$ hearts and $m$ observations per heart,
$$
\operatorname{Var}(\overline Y)=\frac{\sigma_b^2}{H}+\frac{\sigma_e^2}{Hm}.
$$
Adding more measurements to the same heart reduces the second term but not the first. This stipulated model is not a reanalysis of the study's observations; it illustrates how the apparatus and replication structure shape the scientific question.
Morita's verified contribution is coauthorship of that measurement experiment. Its evidence supports the tested preparation and does not establish universal interchangeability of imaging <area> and chamber volume.
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