DNA content equivalence in haploid and diploid maize leaves.

MAIN CONCLUSION: The qPCR assay developed to differentiate haploid and diploid maize leaf samples was unsuccessful due to DNA content difference. Haploid cells are packed more closely together with less cellular expansion. Increased ploidy content (> 2 N) directly correlates with increased cell size in plants, but few studies have examined cell morphology in plants with reduced ploidy (i.e., haploids). To pioneer a scalable new ploidy test, we compared DNA content and cellular morphology of haploid and diploid maize leaves. The amount of genomic DNA recovered from standardized leaf-punch samples was equivalent between these two ploidy types, while both epidermal and mesophyll cell types were smaller in haploid plants. Pavement cells had a substantially smaller size than mesophyll cells, and this effect was more pronounced in the abaxial epidermis. Interveinal distance and guard cell size were significantly reduced in haploids, but the cell percentage comprising stomata did not change. These results confirm the direct correlation between ploidy content and cell size in plants, and suggest that reduced cell expansion predominantly explains DNA content equivalence between haploid and diploid samples, confounding efforts to develop a haploid detection method using DNA content.

A novel method of automated skull registration for forensic facial approximation.

Modern forensic facial reconstruction techniques are based on an understanding of skeletal variation and tissue depths. These techniques rely upon a skilled practitioner interpreting limited data. To (i) increase the amount of data available and (ii) lessen the subjective interpretation, we use medical imaging and statistical techniques. We introduce a software tool, reality enhancement/facial approximation by computational estimation (RE/FACE) for computer-based forensic facial reconstruction. The tool applies innovative computer-based techniques to a database of human head computed tomography (CT) scans in order to derive a statistical approximation of the soft tissue structure of a questioned skull. A core component of this tool is an algorithm for removing the variation in facial structure due to skeletal variation. This method uses models derived from the CT scans and does not require manual measurement or placement of landmarks. It does not require tissue-depth tables, can be tailored to specific racial categories by adding CT scans, and removes much of the subjectivity of manual reconstructions.

Elbow dislocation secondary to fall during police arrest.

A case of total elbow dislocation with significant swelling and loss of distal pulses during police arrest is described. To date, this specific injury in relation to police arrest has not been described in the literature. Whilst attempting to remove the detainee from a public transport vehicle, the patient and the officers involved fell to the ground with his arm slightly flexed. He was handcuffed to the rear and taken to the police office. Whilst there, it was noted that his left elbow was swelling dramatically and he complained of pain. The detainee and officers attended the emergency room and he was found to have a total dislocation of the left elbow and vascular compromise of the limb. The elbow was promptly reduced with sedation and a post reduction angiogram demonstrated injury to the tissues surrounding the brachial artery.