Effect of particle loss on soil behaviour.

Soil particle loss can result in strength and volume reductions which are difficult to predict. This paper investigates the influence of the removal of fractions of selected particle sizes under different confining pressures. The mass loss process was reproduced by the dissolution of selected salt particle sizes and fractions from uniform Leighton Buzzard sand. The dissolution tests were performed in a triaxial cell customised to allow circulation of pore-fluid thereby allowing the dissolution/removal of the salt fraction. Test results from previously conducted oedometric dissolution tests and subsequent triaxial dissolution tests all show increases in void ratio. From the triaxial tests, a reduction in shear strength with increasing ductility was observed. Volumetric and strength behaviour were found to be related to the particle size and fraction material removed while shear-wave measurements obtained pre- and post-particle removal indicate significant changes in small-strain stiffness.

Post-Traumatic Stress Disorder (PTSD) and Its relationship with perinatal bereavement: definitions, reactions, adjustments, and grief.

A small percentage of women present with diagnosed PTSD post childbirth; however, though this an area of increasing research and clinical interest generally, little is known about PTSD in relation to perinatal bereavement. Health professionals must however be aware of the mechanisms and models of loss following perinatal bereavement in order to identify potential mental health phenomena which may be implicated in the development of PTSD symptomology. Understanding the predictive factors which may give early warning signs is an important component of the clinical evidence base. This chapter discusses mechanisms, models, and risk factors in relation to perinatal bereavement and the development of PTSD.