The influence of larval density, food availability and habitat longevity on the life history and population growth rate of the midge Chironomus riparius

Despite long-standing interest in the forms and mechanisms of density dependence, these are still imperfectly understood. However, in a constant environment an increase in density must reduce per capita resource availability, which in turn leads to reduced survival, fecundity and somatic growth rate. Here we report two population experiments examining the density dependent responses under controlled conditions of an important indicator species, Chironomus riparius. The first experiment was run for 35 weeks and was started at low density with replicate populations being fed three different rations. Increased ration reduced generation time and increased population growth rate (pgr) but had no effect on survival, fecundity and female body weight in the first generation. In the second generation there was a six-fold increase in generation time, presumably due to the greatly reduced per capita resource availability as the estimated initial densities of the second generation were 300 times greater than the first. Juvenile survival to emergence, fecundity, adult body weight and pgr declined by 90%, 75%, 35% and 99%, respectively. These large between-generation effects may have obscured the effects of the threefold variation in ration, as only survival to emergence significantly increased with ration in the second generation. These results suggest that some chironomid larvae survive a reduction in resource availability by growing more slowly. In the ephemeral habitats sometimes occupied by C. riparius, the effects of population density may depend crucially on the longevity of the environment. A second experiment was therefore performed to measure pgr from six different starting densities over an eight-week period. The relationship between pgr and density was concave, viewed from above. At densities above 16 larvae per cm(2), less than 1% of the population emerged and no offspring were produced. Under the conditions of experiment 2 - an 8-week habitat lifespan carrying capacity was estimated as 8 larvae per cm(2).

A follow-up study of characteristics of young people that dropout and continue psychotherapy: service implications for a clinic in the community

Background: The paper reports the findings from a follow-up study of the factors that contribute to whether young people dropout or continue once-weekly psychotherapy at a voluntary sector psychotherapy service for young people aged 12 to 21 years. Method: The study uses data from an ongoing audit of the psychotherapy service that started in 1993; 882 young people were included in the study. Premature termination of treatment was defined as dropping out before the 21st session. Continuation in treatment was defined as remaining in therapy after 20 sessions. Measures and areas of interest used in the study include diagnostic measures, the Youth Self Report Form and Young Adult Self Report Form, demographic characteristics and treatment related information. Results: Young people who continued in treatment were more likely to be older, have anxieties about sexual and relationship issues and have higher scores on self-reported anxiety-depression. Young people who dropped out of treatment were more likely to be younger, have higher self-reported delinquency scores, have a diagnosis of hyperactivity-conduct disorder and be homeless. Conclusions: The study of treatment termination has demonstrated the value of service audit and has led to a significant change in clinical practice.

Variability in life-history and ecological traits is a buffer against extinction in mammals

Anthropogenic degradation of the world's ecosystems is leading to a widespread and accelerating loss of biodiversity. However, not all species respond equally to existing threats, raising the question: what makes a species more vulnerable to extinction? We propose that higher intraspecific variability may reduce the risk of extinction, as different individuals and populations within a species may respond differently to occurring threats. Supporting this prediction, our results show that mammalian species with more variable adult body masses, litter sizes, sexual maturity ages and population densities are less vulnerable to extinction. Our findings reveal the role of local variation among populations, particularly of large mammals, as a buffering mechanism against extinction, and emphasise the importance of considering trait variation in comparative analyses and conservation management.

Dwelling in possibility: aestheticizing identity in African American women's fiction

African American women writers define aesthetics through their negotiation of identity in the politicized loci of space, place and voice. In the balkanization of such issues of voice and space, we can see the ways that the emergent selfis embodied and aestheticized in literature. To do so creates a more tactile and "artfull" representation of the self rather than a representation of identity as a mere abstract concept. To use written language to express the self is to carry processes of selfdefinition for black women into the realm of creative production. For women, especially black women, who are a politically and socially compromised element of society, the written word is a way of expressing the politically and the socially critical voice that is suppressed in other forums of expression. Using theories on "writing in difference" as a skeleton key, this project seeks to outline some of the ways that black women writers use aesthetic elements in their art to express the potential for self-examination, discovery, and emancipation.

Raising the subject : ideology in children's fiction

This thesis is concerned to reveal, by means of textual analysis, ideologies connected to human subjectivity within eight contemporary novels for 'children' . The analyses draw upon the work of Macherey, Eagleton, Jameson and Bakhtin among others. The texts discussed cover more than two decades, from 1955 to 1977. The first, Philippa Pearce's Minnow on the Say, attempts to reconcile a traditional form of subjectivity with a less hierarchic and mare open type. Lyotard's account of customary and scientific knowledge, and Said's of affiliation ion , are the basis for discussion here. Susan Cooper's sequence The Dark is Rising grounds humanism in a mythic British past. Within these texts the problem of situating the subject within a wider social framework is linked to one of nationalism. Her novels are fantasies, and provide an opportunity for a discussion of a non-realist form and its ideological implications, Todorov's account of the fantastic as a genre is a reference—point in this analysis. Jane Garden’s Bilge water presents a discontinuous subject—in-process. Her story is told by a first— person narrator, situated within a framed narrative. Through its themes and structures the text interrogates its central character's project of subjectivity as perfectible, centered and continuous, and finds it untenable. In Russell Hagan’s The House and his Child the possibility of self-determination within language as discourse is of central concern. The tin mice, who are hollow, echo in their persons the text's interest in the distinction between inside and outside, the difference which Lacanian theory posits as essential for an accession to subjectivity- Hoban's work gives an account of the postmodern subject, and calls into question the subjectivities assumed in Pearce's and Cooper's texts.

(Post)colonial ambivalences : Christina Stead and Janet Frame

This thesis is an evaluative comparison of two significant writers, the Australian Christina Stead, and New Zealander Janet Frame. In a detailed analysis of the novels, the writerly ambivalences of each author are explored. Their writings are revealed to be creative of new possibilities for female (post)colonial agency.

Papers from Marrakech : a post-colonial reading of western women's travel writing in North Africa and the Middle East

This thesis takes the form of a collection of theoretical and fictional documents comprising a journal, letters and essays sent home to Australia by a woman travelling in Morocco. In different modes, these papers examine issues of colonialism, gender and desire in western women's travel writing about North Africa and the Middle East.

Prose fiction’s infinite playlist : encountering music in fiction narrative

This paper will argue that reference to music in young-adult prose fiction stimulates movement across narrative and artistic boundaries in ways that facilitate a unique reading encounter. The inclusion of musical reference opens up a space for a multisensory experience that is beyond that of the reading experience devoid of musical association, even when the audio is not immediately available at the time of reading. This experience is bound to the role of the reader, however, be it through the remembered or imagined experience of the music that is signaled in-text, or even the reader’s pursuit of the audio in response to the reading. As ‘a threshold literature’ (Eaton 2010, np) that targets a young audience for whom ‘popular music is globally acknowledged as affectively and culturally central’ (Bloustien & Peters 2011, 4), young-adult fiction is an apt space for explorations into the potential that exists when a text includes musical reference. In particular, Gerard Genette’s paratexts (1997), J Hillis Miller’s ‘membranes’ (2005) and T Austin Graham’s ‘literary soundtrack’ (2009) will be used to examine how Rachel Cohn and David Levithan’s young-adult fiction novel Nick and Norah’s infinite playlist (2006) functions as an ‘infinite playlist’ in itself via a series of paratextual and epitextual elements. Discussion of the latticework of music-narrative interaction that exists as a part of this text will facilitate an understanding of how musical reference can encourage movement within and beyond the narrative towards a potentially unique reading experience.

Young adult voting decision-making: Studying the effect of usage from a consumer behaviour perspective

This study investigates the application of consumer behaviour theory to young Australian adults’ voting decision-making. Previous decision-making studies identified constructs of subjective knowledge, involvement, information seeking, satisfaction, confidence, and stability as key factors in voting decision-making. This research tests the relationship that these factors have with the consumer behaviour concept of usage. A new concept, commitment to vote, is also considered for Australia’s compulsory voting context. Data were gathered from a sample of 257 Australian citizens between the ages of 18 and 25. Exploratory factor analysis produced nine factors, and MANOVA and ANOVA were used to test the differences between three usage groups: voluntary users, involuntary users, and never trieds. The results illustrate that usage has a significant influence on information seeking, commitment to voting, satisfaction with voting choice, and stability in voting decision-making. Therefore, usage is a key element in voter decision-making and needs to be included in future studies.

Young adult sequelae of adolescent cannabis use: an integrative analysis

 Background: Debate continues about the consequences of adolescent cannabis use. Existing data are limited in statistical power to examine rarer outcomes and less common, heavier patterns of cannabis use than those already investigated; furthermore, evidence has a piecemeal approach to reporting of young adult sequelae. We aimed to provide a broad picture of the psychosocial sequelae of adolescent cannabis use. Methods: We integrated participant-level data from three large, long-running longitudinal studies from Australia and New Zealand: the Australian Temperament Project, the Christchurch Health and Development Study, and the Victorian Adolescent Health Cohort Study. We investigated the association between the maximum frequency of cannabis use before age 17 years (never, less than monthly, monthly or more, weekly or more, or daily) and seven developmental outcomes assessed up to age 30 years (high-school completion, attainment of university degree, cannabis dependence, use of other illicit drugs, suicide attempt, depression, and welfare dependence). The number of participants varied by outcome (N=2537 to N=3765). Findings: We recorded clear and consistent associations and dose-response relations between the frequency of adolescent cannabis use and all adverse young adult outcomes. After covariate adjustment, compared with individuals who had never used cannabis, those who were daily users before age 17 years had clear reductions in the odds of high-school completion (adjusted odds ratio 0·37, 95% CI 0·20-0·66) and degree attainment (0·38, 0·22-0·66), and substantially increased odds of later cannabis dependence (17·95, 9·44-34·12), use of other illicit drugs (7·80, 4·46-13·63), and suicide attempt (6·83, 2·04-22·90). Interpretation: Adverse sequelae of adolescent cannabis use are wide ranging and extend into young adulthood. Prevention or delay of cannabis use in adolescence is likely to have broad health and social benefits. Efforts to reform cannabis legislation should be carefully assessed to ensure they reduce adolescent cannabis use and prevent potentially adverse developmental effects. Funding: Australian Government National Health and Medical Research Council. © 2014 Elsevier Ltd.

Evaluating young adult voter decision-making involvement within a compulsory political system

Purpose - This study aims to specifically focus on the lower-involvement young adult voters within the Australian compulsory voting context. It explores voters’ political decision-making by considering the influence of the consumer behaviour theory of involvement. Design/methodology/approach - A thematic analysis was conducted to analyse the interviews within the two research questions: information seeking and decision-making. Findings - Key themes within information seeking are the reach of the information available, the frequency of the information presented, the creativity of the message and one-way versus two-way communication. Key themes within evaluation are promise keeping/trust, achievements or performance and policies. Lower-involvement decision-making has the potential to be a habitual, limited evaluation decision. However, issues of trust, performance and policies may encourage evaluation, thereby reducing the chances of habitually voting for the same party as before. Practical implications - This new area of research has implications for the application of marketing for organisations and political marketing theory. Considering voting decision-making as a lower-involvement decision has implications for assisting the creation and adaptation of strategies to focus on this group of the population. Originality/value - The compulsory voting environment creates a unique situation to study lower-involvement decision-making, as these young adults are less likely to opt out of the voting process. Previous research in political marketing has not specifically explored the application of involvement to young adult voting within a compulsory voting environment.

The role of a care-orientation in the teens in young adult psychosocial wellbeing

Abstract
The transition from adolescence to young adulthood is a watershed period in development that carries risk for poor psychosocial adjustment. It also carries potential for positive transitions into the caregiving roles and responsibilities of adult life. Research to date has predominantly focused on adolescent predictors of problematic rather than positive transitions; yet predictors of the latter hold equal (if not greater) promise for informing health promoting interventions. The purpose of this study was threefold: (1) to use Latent Profile Analysis (LPA) to define patterns of psychosocial adjustment and maladjustment in young adulthood (21-years of age); (2) to examine the unique role of adolescent prosocial behaviour (e.g., volunteering and civic engagement) in promoting adjustment and reducing maladjustment in young adulthood; and, (3) to examine whether protective developmental relationships are maintained after adjustment for other covariates including socio-economic background factors and personality characteristics. Data were drawn from the Victorian cohort of the International Youth Development Study (IYDS; N = 2407), a representative sample of students in Victoria, Australia. Students were assessed in Grade 9 (Mean age = 15-years) and followed up at age 21-years. LPA identified three psychosocial adjustment classes at age 21 defined as: (1) Adjusted (24.8 %); (2) Normative (63.9 %); and, (3) Maladjusted (11.3 %). Adolescent volunteering, belief in a moral order, family opportunities for prosocial behaviour, and commitment to school were associated with enhanced adjustment and reduced maladjustment in young adulthood. Findings highlight the potential benefit of interventions designed to enhance adolescent prosocial behaviours and care orientation in promoting healthy transitions into young adult life.