Biomedical subjects

E B Vedel Jensen

Publications and source records attributed to E B Vedel Jensen.

4 recordsLinked to original sources

PubMed2006

A note on the stereological implications of irregular spacing of sections.

Stereological methods for serial sections traditionally assume that the sections are exactly equally spaced. In reality, the spacing and thickness of sections can be quite irregular. This may affect the validity and accuracy of stereological techniques, especially the Cavalieri estimator of volume. We present a new formula for the accuracy of the Cavalieri estimator that includes the effect of random variability in section spacing. A modest amount of variability in section spacing can cause a substantial increase in estimator variance.

Analysis of Variance↗

PubMed2006

On error prediction in circular systematic sampling.

An extended covariogram model is discussed for estimating the precision of circular systematic sampling. The extension is motivated by recent developments in shape analysis of featureless planar objects. Preliminary simulation results indicate that it is important to consider the extended covariogram model.

Journal Article↗

PubMed2004

Volume estimation from projections.

We describe a new estimator of the volume of axially convex objects from total vertical projections with known position of the vertical axis. The estimator combines the Cavalieri method with the known formula for area in terms of the support function of a convex body. We examine the accuracy of the proposed estimator for ellipsoidal objects having exactly known support function and volume. In addition, we illustrate practical problems of accuracy by implementing the method for some biological products.

Biology↗

PubMed2004

Shape modelling of spatial particles from planar central sections -- a case study.

In this paper we develop statistical tools for shape modelling of spatial particles from central sections through the particles. The particles are assumed to be star-shaped with respect to a reference point inside the particles and are modelled as stochastic deformations of spheres centred at the reference points. The resulting particles are rotation invariant with respect to the reference point. As an illustration, the model is applied to study shape differences between neurons in the Granular and CA1 layer in the human hippocampus.

Animals↗