Shifting : one-inclusion mistake bounds and sample compression

We present new expected risk bounds for binary and multiclass prediction, and resolve several recent conjectures on sample compressibility due to Kuzmin and Warmuth. By exploiting the combinatorial structure of concept class F, Haussler et al. achieved a VC(F)/n bound for the natural one-inclusion prediction strategy. The key step in their proof is a d = VC(F) bound on the graph density of a subgraph of the hypercube—oneinclusion graph. The first main result of this paper is a density bound of n [n−1 <=d-1]/[n <=d] < d, which positively resolves a conjecture of Kuzmin and Warmuth relating to their unlabeled Peeling compression scheme and also leads to an improved one-inclusion mistake bound. The proof uses a new form of VC-invariant shifting and a group-theoretic symmetrization. Our second main result is an algebraic topological property of maximum classes of VC-dimension d as being d contractible simplicial complexes, extending the well-known characterization that d = 1 maximum classes are trees. We negatively resolve a minimum degree conjecture of Kuzmin and Warmuth—the second part to a conjectured proof of correctness for Peeling—that every class has one-inclusion minimum degree at most its VCdimension. Our final main result is a k-class analogue of the d/n mistake bound, replacing the VC-dimension by the Pollard pseudo-dimension and the one-inclusion strategy by its natural hypergraph generalization. This result improves on known PAC-based expected risk bounds by a factor of O(logn) and is shown to be optimal up to an O(logk) factor. The combinatorial technique of shifting takes a central role in understanding the one-inclusion (hyper)graph and is a running theme throughout.

Shifting : one-inclusion mistake bounds and sample compression

We present new expected risk bounds for binary and multiclass prediction, and resolve several recent conjectures on sample compressibility due to Kuzmin and Warmuth. By exploiting the combinatorial structure of concept class F, Haussler et al. achieved a VC(F)/n bound for the natural one-inclusion prediction strategy. The key step in their proof is a d=VC(F) bound on the graph density of a subgraph of the hypercube—one-inclusion graph. The first main result of this report is a density bound of n∙choose(n-1,≤d-1)/choose(n,≤d) < d, which positively resolves a conjecture of Kuzmin and Warmuth relating to their unlabeled Peeling compression scheme and also leads to an improved one-inclusion mistake bound. The proof uses a new form of VC-invariant shifting and a group-theoretic symmetrization. Our second main result is an algebraic topological property of maximum classes of VC-dimension d as being d-contractible simplicial complexes, extending the well-known characterization that d=1 maximum classes are trees. We negatively resolve a minimum degree conjecture of Kuzmin and Warmuth—the second part to a conjectured proof of correctness for Peeling—that every class has one-inclusion minimum degree at most its VC-dimension. Our final main result is a k-class analogue of the d/n mistake bound, replacing the VC-dimension by the Pollard pseudo-dimension and the one-inclusion strategy by its natural hypergraph generalization. This result improves on known PAC-based expected risk bounds by a factor of O(log n) and is shown to be optimal up to a O(log k) factor. The combinatorial technique of shifting takes a central role in understanding the one-inclusion (hyper)graph and is a running theme throughout

Group maintenance scheduling : a case study for a pipeline network

This paper presents a group maintenance scheduling case study for a water distributed network. This water pipeline network presents the challenge of maintaining aging pipelines with the associated increases in annual maintenance costs. The case study focuses on developing an effective maintenance plan for the water utility. Current replacement planning is difficult as it needs to balance the replacement needs under limited budgets. A Maintenance Grouping Optimization (MGO) model based on a modified genetic algorithm was utilized to develop an optimum group maintenance schedule over a 20-year cycle. The adjacent geographical distribution of pipelines was used as a grouping criterion to control the searching space of the MGO model through a Judgment Matrix. Based on the optimum group maintenance schedule, the total cost was effectively reduced compared with the schedules without grouping maintenance jobs. This optimum result can be used as a guidance to optimize the current maintenance plan for the water utility.

Supportive-expressive group therapy for women with metastatic breast cancer: Improving access for Australian women through use of teleconference

While supportive-expressive group therapy (SEGT) has been found to be effective in significantly reducing distress associated with life-threatening illness, the challenge in Australia is to develop a means of providing supportive interventions to rural women who may be isolated both by the experience of illness and by geographical location. In this study an adaptation of SEGT was provided to women with metastatic breast cancer (n =21), who attended face-to-face or by telephone conference call. Participants showed significant gains on standardised measures of well-being, including a reduction in negative affect and an increase in positive affect, over a 12-month period. A reduction in intrusive and avoidant stress symptoms was also observed over 12 months; however, this difference was not significant. These outcomes suggest that SEGT, delivered in an innovative way within a community setting, may be an effective means of moderating the adverse effects of a diagnosis of metastatic breast cancer while improving access to supportive care for rural women. These results are considered exploratory, as the study did not include a matched control group.

Diversity in action : minority group media and social change

My thesis consists of a creative work plus an exegesis. This exegesis uses case study research to investigate three Brisbane-based media organisations and the role they play in encouraging social inclusion and other positive social change for specific disadvantaged and stigmatised minority groups. Bailey, Cammaerts and Carpentier’s theoretical approach to alternative media forms the basis of this research. Bailey et al. (2008, p. 156) view alternative media organisations as having four important roles, two media-centred and two society-centred, which must all be considered to best understand them: • serving their communities • acting as an alternative to mainstream media discourses • promoting and advocating democratisation in the media and through the media in society • functioning as a crossroads in civil society. The first case study, about community radio station 4RPH (Radio for the Print Handicapped), centres on promoting social inclusion for people with a print disability through access to printed materials (primarily mainstream print media) in an audio format. The station also provides important opportunities for members of this group to produce media and, to a lesser extent, provides disability-specific information and discussions. The second case study, about gay print and online magazine Queensland Pride, focuses on promoting social inclusion and combating the discrimination and repression of people who identify as lesbian, gay, bisexual or transgender. Central issues include the representation (including sexualised representation) of a subculture and niche target market, and the impact of commercialisation on this free publication. The third case study, about community radio station 98.9FM, explores the promotion of social inclusion for peoples whose identity, cultures, issues, politics and contributions are often absent or misrepresented in the mainstream media. This radio station provides “a first level of service” (Meadows & van Vuuren, 1998, p. 104) to these people, but also informs and entertains those in the majority society. The findings of this research suggest that there are two key mechanisms that help these media organisations to effect social change: first, strengthening the minority community and serving its needs, and second, fostering connections with the broader society.

Exploiting the 1,2,3-triazolium motif in anion-templated formation of a bromide-selective rotaxane host assembly

Stimulated by the efficacy of copper (I) catalysed Huisgen-type 1,3-dipolar cycloaddition of terminal alkynes and organic azides to generate 1,4-disubstituted 1,2,3-triazole derivatives, the importance of ‘click’ chemistry in the synthesis of organic and biological molecular systems is ever increasing.[1] The mild reaction conditions have also led to this reaction gaining favour in the construction of interlocked molecular architectures.[2-4] In the majority of cases however, the triazole group simply serves as a covalent linkage with no function in the resulting organic molecular framework. More recently a renewed interest has been shown in the transition metal coordination chemistry of triazole ligands.[3, 5, 6] In addition novel aryl macrocyclic and acyclic triazole based oligomers have been shown to recognise halide anions via cooperative triazole C5-H….anion hydrogen bonds.[7] In light of this it is surprising the potential anion binding affinity of the positively charged triazolium motif has not, with one notable exception,[8] been investigated. With the objective of manipulating the unique topological cavities of mechanically bonded molecules for anion recognition purposes, we have developed general methods of using anions to template the formation of interpenetrated and interlocked structures.[9-13] Herein we report the first examples of exploiting the 1,2,3-triazolium group in the anion templated formation of pseudorotaxane and rotaxane assemblies. In an unprecedented discovery the bromide anion is shown to be a superior templating reagent to chloride in the synthesis of a novel triazolium axle containing [2]rotaxane. Furthermore the resulting rotaxane interlocked host system exhibits the rare selectivity preference for bromide over chloride...

Nitrone [2]rotaxanes: Simultaneous chemical protection and electrochemical activation of a functional group

We report on the use of the hydrogen bond accepting properties of neutral nitrone moieties to prepare benzylic-amide-macrocycle-containing [2]rotaxanes in yields as high as 70 %. X-Ray crystallography shows the presence of up to four intercomponent hydrogen bonds between the amide groups of the macrocycle and the two nitrone groups of the thread. Dynamic 1H NMR studies of the rates of macrocycle pirouetting in nonpolar solutions indicate that amide-nitrone hydrogen bonds are particularly strong, ~1.3 and ~0.2 kcal mol-1 stronger than similar amide-ester and amide-amide interactions, respectively. In addition to polarizing the N-O bond through hydrogen bonding, the rotaxane structure affects the chemistry of the nitrone groups in two significant ways: The intercomponent hydrogen bonding activates the nitrone groups to electrochemical reduction, a one electron reduction of the rotaxane being stablized by a remarkable 400 mV (8.1 kcal mol-1) with respect to the same process in the thread; encapsulation, however, protects the same functional groups from chemical reduction with an external reagent (and slows down electron transfer to and from the electroactive groups in cyclicvoltammetry experiments). Mechanical interlocking with a hydrogen bonding molecular sheath thus provides a route to an encapsulated polarized functional group and radical anions of significant kinetic and thermodynamic stability.

Evaluating parent-child group music therapy programmes: challenges and successes for Sing & Grow

Sing & Grow is an early intervention music therapy programme for families with children from birth to 3 years of age, who are socially, economically, or physically disadvantaged. It aims to improve parenting skills and confidence, promote positive parent–child interactions, stimulate child development, and provide social networking opportunities. Music and song activities are used in a therapeutic context to enhance parenting skills, improve parent–child interactions, provide essential developmental stimulation for children, promote social support for parenting, and strengthen links between parents and community services.

The influence of conformity and group identity on drink walking intentions : comparing intentions to drink walk across risky pedestrian crossing scenarios

Despite the dangers associated with drink walking, limited research is currently available regarding the factors which influence individuals to engage in this risky behaviour. This study examined the influence of psychosocial factors upon individuals’ intentions to drink walk across four experimental scenarios (and a control condition). Specifically, a 2 × 2 repeated measures design was utilised in which all of the scenarios incorporated a risky pedestrian crossing situation (i.e., a pedestrian crossing against a red man signal) but differed according to the level of group identity (i.e., low/strangers and high/friends) and conformity (low and high). Individuals were assessed for their intentions to drink walk within each of these different scenarios. Undergraduate students (N = 151), aged 17–30 years, completed a questionnaire. Overall, most of the study's hypotheses were supported with individuals reporting the highest intentions to drink walk when in the presence of friends (i.e., high group identity) and their friends were said to be also crossing against the red man signal (i.e., high conformity). The findings may have significant implications for the design of countermeasures to reduce drink walking. For instance, the current findings would suggest that potentially effective strategies may be to promote resilience to peer influence as well as highlight the negative consequences associated with following the behaviour of other intoxicated pedestrians who are crossing against a red signal.

The effectiveness of a short-term group music therapy intervention for young parents and their children

The quality of early life experiences are known to influence a child’s capacities for emotional, social, cognitive and physical competence throughout their life (Peterson, 1996; Zubrick et al., 2008). These early life experiences are directly affected by parenting and family environments. A lack of positive parenting has significant implications both for children, and the broader communities in which they live (Davies & Cummings, 1994; Dryfoos, 1990; Sanders, 1995). Young parents are known to be at risk of experiencing adverse circumstances that affect their ability to provide positive parenting to their children (Milan et al., 2004; Trad, 1995). There is a need to provide parenting support programs to young parents that offer opportunities for them to come together, support each other and learn ways to provide for their children’s developmental needs in a friendly, engaging and non-judgemental environment. This research project examines the effectiveness of a 10 week group music therapy program Sing & Grow as an early parenting intervention for 535 young parents. Sing & Grow is a national early parenting intervention program funded by the Australian Government and delivered by Playgroup Queensland. It is designed and delivered by Registered Music Therapists for families at risk of marginalisation with children aged from birth to three years. The aim of the program is to improve parenting skills and parent-child interactions, and increase social support networks through participation in a group that is strengths-based and structured in a way that lends itself to modelling, peer learning and facilitated learning. During the 10 weeks parents have opportunities to learn practical, hands-on ways to interact and play with their children that are conducive to positive parent-child relationships and ongoing child development. A range of interactive, nurturing, stimulating and developmental music activities provide the framework for parents to interact and play with their children. This research uses data collected through the Sing & Grow National Evaluation Study to examine outcomes for all participants aged 25 years and younger, who attended programs during the Sing & Grow pilot study and main study from mid-2005 to the end of 2007. The research examines the change from pre to post in self-reported parent behaviours, parent mental health and parent social support, and therapist observed parent-child interactions. A range of statistical analyses are used to address each Research Objective for the young parent population, and for subgroups within this population. Research Objective 1 explored the patterns of attendance in the Sing & Grow program for young parents, and for subgroups within this population. Results showed that levels of attendance were lower than expected and influenced by Indigenous status and source of family income. Patterns of attendance showed a decline over time and incomplete data rates were high which may indicate high dropout rates. Research Objective 2 explored perceived satisfaction, benefits and social support links made. Satisfaction levels with the program and staff were very high. Indigenous status was associated with lower levels of reported satisfaction with both the program and staff. Perceived benefits from participation in the program were very high. Employment status was associated with perceived benefits: parents who were not employed were more likely than employed parents to report that their understanding of child development had increased as a result of participation in the program. Social support connections were reported for participants with other professionals, services and parents. In particular, families were more likely to link up with playgroup staff and services. Those parents who attended six or more sessions were significantly more likely to attend a playgroup than those who attended five sessions or less. Social support connections were related to source of family income, level of education, Indigenous status and language background. Research Objective 3 investigated pre to post change on self-report parenting skills and parent mental health. Results indicated that participation in the Sing & Grow program was associated with improvements in parent mental health. No improvements were found for self-reported parenting skills. Research Objective 4 investigated pre to post change in therapist observation measures of parent-child interactions. Results indicated that participation in the Sing & Grow program was associated with large and significant improvements in parent sensitivity to, engagement with and acceptance of the child. There were significant interactions across time (pre to post) for the parent characteristics of Indigenous status, family income and level of education. Research Objective 5 explored the relationship between the number of sessions attended and extent of change on self-report outcomes and therapist observed outcomes, respectively. For each, an overall change score was devised to ascertain those parents who had made any positive changes over time. Results showed that there was no significant relationship between high attendance and positive change in either the self-report or therapist observed behavioural measures. A risk index was also constructed to test for a relationship between the risk status of the parent. Parents with the highest risk status were significantly more likely to attend six or more sessions than other parents, but risk status was not associated with any differences in parent reported outcomes or therapist observations. The results of this research study indicate that Sing & Grow is effective in improving outcomes for young parents’ mental health, parent-child interactions and social support connections. High attendance by families in the highest category for risk factors may indicate that the program is effective at engaging and retaining parents who are most at-risk and therefore traditionally hard to reach. Very high levels of satisfaction and perceived benefits support this. Further research is required to help confirm the promising evidence from the current study that a short term group music therapy program can support young parents and improve their parenting outcomes. In particular, this needs to address the more disappointing outcomes of the current research study to improve attendance and engagement of all young parents in the program and especially the needs of young Indigenous parents.