Quantitative assessment of through-thickness crack size based on Lamb wave scattering in aluminium plates

The interaction of Lamb wave modes at varying frequencies with a through-thickness crack of different lengths in aluminium plates was analysed in terms of finite element method and experimental study. For oblique-wave incidence, both numerical and experimental results showed that the wave scattering from a crack leads to complicated transmission, reflection and diffraction accompanied by possible wave-mode conversion. A dual-PZT actuation scheme was therefore applied to generate the fundamental symmetrical mode (S0) with enhanced energy to facilitate the identification of crack-scattered wave components. The relationship between crack length and the reflection/transmission coefficient obtained with the aid of the Hilbert transform was established, through which the crack length was quantitatively evaluated. The effects of wavelength of Lamb waves and wave diffraction on the properties of the reflection and transmission coefficients were analysed.

Activation of the hypothalamo-pituitary-adrenal axis by isolation and restraint stress during lactation in ewes : effect of the presence of the lamb and suckling

We investigated the effect of the presence and absence of lambs and suckling by lambs to attenuate activation of the hypothalamo-pituitary-adrenal (HPA) axis to isolation and restraint stress in lactating sheep. In experiment 1, blood samples were collected every 10 min from nonlactating (n = 5) and lactating (n = 5) ewes for 4 h before and during stress. In experiment 2, ewes (n = 6) were allocated to 1) nonlactating, 2) lactating with lambs absent, 3) lactating with lambs present but unable to suckle, and 4) lactating with lambs present and able to suckle. Blood samples were collected over 8 h with no stress (control day) and for 4 h before and 4 h during stress (stress day). In experiment 1, the mean (±SEM) cortisol concentrations increased significantly (P < 0.05) in nonlactating ewes during stress but did not change in lactating ewes. In experiment 2, cortisol did not vary on the control day or pretreatment of the stress day but increased (P < 0.05) during stress in all groups except lactating ewes with lambs present and able to suckle. The greatest cortisol response occurred in nonlactating ewes followed by lactating ewes with lambs absent and lactating ewes with lambs present but unable to suckle. During stress, the ACTH concentrations increased (P < 0.05) in nonlactating ewes and lactating ewes with lambs absent but not in lactating ewes with lambs present. We conclude that the activity of the HPA axis during isolation and restraint is reduced in lactating ewes and that the presence of lambs increases this level of attenuation.

'Friend of my soul' : constructing spiritual friendship in the autobiography of Mary Fletcher

Mary Bosanquet Fletcher (1739-1815) was a leading early English Methodist, active throughout her adult life as a preacher, author, spiritual director and head of a large household. She was also part of a largely unexamined network of intense and intimate friendships between Methodist women across England. This article analyses the ways in which Fletcher represented friendship in her autobiography, a text that was widely published and read throughout the nineteenth century. Fletcher's autobiography shows how religious conviction could shape a distinctive construction of female friendship, at a time when such friendships had growing social and cultural significance.

Warrnambool's Wesleyan heritage, 1847-1977

The thesis is about Methodism in Warrnambool. The key argument is that the Wesleyan heritage, so important to the early Wesleyan pioneers, continued to shape the life of the Warrnambool Methodist Church and was perpetuated by its leaders, in particular its local lay leaders, for a period of 130 years.

Transformations : landscape in recent Australian fiction / Gillian Mary Tyas

Focusing on novels written since 1980 by Australian authors Rodney Hall, Liam Davison, Tim Winton, Elizabeth Jolley and Gerald Murnane, and engaging with responses to the land by visual and performing artists, this thesis explores the idea that the writer and artist are mediators in the multitude of experiences that constitutes landscape.

Mary De Garis

The thesis is a biographical study of the life and times of Dr Mary De Garis, (1881-1963) an early medical woman. It examines her extensive writing, her research on childbirth and her modernising of the Geelong Hospital in the 1920s and 1930s. Her life illuminates Australian women in the first half of the twentieth century.