Edward Gosden

Seasonal morphometry of the vomeronasal organ in the marsupial mouse, Antechinus subtropicus.

The vomeronasal system consists of a peripheral organ and the connected central neuronal networks. The central connections are sexually dimorphic in rodents, and in some species, parameters of the vomeronasal organ (VNO) vary with sex, hormonal exposure, body size and seasonality. The VNO of the dasyurid marsupial mouse, Antechinus subtropicus is presumed to be functional. The unusual life history (male semelparity) is marked by distinct seasonality with differences in hormonal environments both between males and females, and in males at different time points. Body size parameters (e.g., length, weight) display sexual dimorphism and, in males, a pronounced weight gain before breeding is followed by a rapid decline during the single, short reproductive season. VNO morphometry was investigated in male and female A. subtropicus to identify possible life cycle associated activity. The overall length of the VNO is positively correlated with the size of the animal. The amount of sensory epithelium exhibits a negative correlation, decreasing with increasing size of the animal. The effects of sex and breeding condition are not obvious, although they do suggest that sensory vomeronasal epithelium mass declines in the breeding period. The VNO may be more important in A. subtropicus before breeding when it may participate in synchronising reproduction and in the development of the male stress response. J. Morphol. 277:1517–1530, 2016.

Review article: Diagnostic accuracy of risk stratification tools for patients with chest pain in the rural emergency department: A systematic review.

Risk stratification tools for patients presenting to rural EDs with undifferentiated chest pain enable early definitive treatment in high‐risk patients. This systematic review compares the most commonly used risk stratification tools used to predict the risk of major adverse cardiac event (MACE) for patients presenting to rural EDs with chest pain. A comprehensive search of MEDLINE and Embase for studies published between January 2011 and January 2015 was undertaken. Study quality was assessed using QUADAS‐2 criteria and the PRISMA guidelines.Eleven studies using eight risk stratification tools met the inclusion criteria. The percentage of MACE in the patients stratified as suitable for discharge, and the percentage of patients whose scores would have recommended admission that did not experience a MACE event were used as comparisons. Using the findings of a survey of emergency physicians that found a 1% MACE rate acceptable in discharged patients, the EDACS‐ADP was considered the best performer. EDACS‐ADP had one of the lowest rates of MACE in those discharged (3/1148, 0.3%) and discharged one of the highest percentage of patients (44.5%). Only the GRACE tool discharged more patients (69% – all patients with scores <100) but had a MACE rate of 0.3% in discharged patients. The HFA/CSANZ guidelines achieved zero cases of MACE but discharged only 1.3% of patients.EDACS‐ADP can potentially increase diagnostic efficiency of patients presenting at ED with chest pain. Further assessment of tool in a rural context is recommended.

Development and Validation of a Technique for Casting Anatomical Features and Toolmarks

Time may elapse between examination of marks inflicted on the body and comparison with a potential weapon. Two‐dimensional photographs may be inadequate for effective comparison of a three‐dimensional mark with a putative instrument. Taking a cast and producing a positive image results in a lasting three‐dimensional record. This project aimed to develop and demonstrate the accuracy of an easy technique for production of long‐lasting positive images (using plaster of Paris and dental alginate). Casts of facial features of embalmed cadavers were used to produce a positive image of the face (death mask). Measurements of distances between facial anatomical landmarks were compared with measurements of distances between the same landmarks on the death masks to assess accuracy of reproduction. There were no significant differences between cadaver and death mask in 6 of 9 measurements, indicating this technique has high accuracy with less mobile facial features, but produces deformation of pliable features.

Quantitative Sex Identification of Hatchling Green Sea Turtles (Chelonia mydas)

Abstract The histological characteristics of the gonads and paramesonephric ducts were investigated to allow a quantitative distinction among male, female, and intersex hatchling Green Sea Turtles (Chelonia mydas) from peninsular Malaysia. Hatchling sexes were identified initially as either males or females based on the incubation temperatures, and intersex hatchlings were collected from in situ nests. Traditionally, this assignment is confirmed by qualitative visual assessment of histological sections of the gonads and paramesonephric ducts. We describe a quantitative method for measuring these parameters to distinguish hatchling sex. The thickness of the paramesonephric duct epithelium area, the height of the nucleus in cells within the gonadal cortical epithelium, and the width of the gonadal ridge were measured in sections from 116 hatchlings. Upon examination of the histological material, hatchlings identified initially by incubation temperature as females were found to have significantly thicker paramesonephric duct epithelium and greater gonadal ridge width and cortical epithelium nuclear height compared with hatchlings identified as males. In addition, some hatchlings demonstrated histological characteristics of both sexes (designated here as intersex hatchlings) in some or all of the traditional histological sexing criteria. The “intersex” group could be divided into two subgroups by the quantitative measurements described here. Using this method, hatchlings could be classified as either males, females, or intersexes with a male-appearing gonad and female-appearing duct or a female-appearing gonad and male-appearing duct. The method outlined here provides a quantitative way to distinguish sex and provides insight in intersex grouping in hatchling C. mydas.