A Study of Order-by-Disorder Phenomenon in Frustrated Magnetic Systems Near Criticality

Order-by-disorder is the phenomenon of the selection of a long-ranged ordered state by fluctuations in a many-body system. This mechanism, at first sight, seems paradoxical, since fluctuations (disorder) intuitively tend to suppress the order. However, when ObD happens, disorder works in favour of a particular ordered phase. Order-by-disorder can happen where an accidental degeneracy occurs in classical or mean field treatment of a system. These degeneracies, which are not due to exact symmetries of the system, can then be lifted by quantum or thermal fluctuations. The ObD phenomenon is ubiquitous in condensed matter systems with competing or frustrated interactions. Traditionally, the ObD is studied at $T = 0^+$ where the ground state of the system can be selected by quantum fluctuations. The study of ObD at temperature regimes near criticality, $T \lesssim Tc$ where transition happens from the paramagnetic phase to an ordered phase, however, have not received as much attention. In this thesis, we study the ObD phenomenon in three dimensional frustrated sys- tems close to criticality. We consider 3-component classical Heisenberg spins on pyrochlore lattice and FCC lattice. In the former, the spins interact via a Hamiltonian that can include the most general nearest-neighbour symmetry allowed bilinear interactions, long- range magnetostatic dipole-dipole interaction and second and/or third nearest-neighbour exchange interactions. However, in the latter, the Hamiltonian only consists of long-range magnetostatic dipole-dipole interactions. These two systems, correspond to insulating rare- earth pyrochlore oxides and rare-earth FCC salts. The mean field treatment shows, that accidental $O(4)$ and $U(1)$ symmetries emerge in two different regions of the parameter space of the Hamiltonian of pyrochlore system. While in the FCC system, an accidental $O(3)$ symmetry emerges at the mean field level. We show that fluctuations break these symmetries by respectively introducing cubic (in 4-vector and 3-vector models) and hexag- onal anisotropies to the free-energy of the system. To study these system beyond mean field approximation, we use Monte Carlo simulations, spin wave theory and we develop the E-TAP method which is an extended version of the method originally proposed by Thouless, Anderson and Palmer to study fluctuations in spin glasses

A survey of child care centers about breastfeeding support in Adelaide, South Australia.

Author's version made available in accordance with Publisher's copyright policy.Background: Australia has high rates of breastfeeding initiation, with a consistent decline over the first year. Furthermore, there is a growing trend of maternal employment and rising numbers of children enrolled in different types of child care services, both of which can have a negative impact on breastfeeding. Objectives: To provide evidence to better inform implementation of breastfeeding-friendly strategies in child care settings, this study examined breastfeeding policy and practice in child care centers in metropolitan Adelaide. Methods: The paper reports on a survey sent to 292 child care centers in metropolitan Adelaide in 2010. The survey collected information on center location and type, number of enrolled children under age 2, and number of breastfed babies. The survey also included questions about breastfeeding facilities and support, breastfeeding policies, staff training, and barriers to and recommendations to enhance breastfeeding support in child care centers. Results: Of the 62 completed returned surveys (21% response rate), 43 centers (69.4%) reported that they currently have children who receive breast milk at the center; however, in most centers, the total number of breastfed children was reported to be between 1 and 4; 76% reported that the center was supportive of exclusive breastfeeding for 6 months; and 80.6% had statements on breastfeeding as part of their food and nutrition policies or guidelines. Furthermore, 64.5% reported there was no formal or informal training for staff on breastfeeding support, but 50% reported that staff members do provide breastfeeding advice to mothers of children in their center. Conclusions: Despite some strategies in place to support breastfeeding, there are no standards on breastfeeding policies, practices, and training in child care settings.Therefore, the extent and scope of such support depend on parental request and the perceptions and attitudes of child care center staff toward breastfeeding

Quantum Phase Transition in Triple Quantum Dot System and Its Consequences on Transport

In this thesis, possibility of quantum phase transition in systems composed of quantum dots will be studied. We also investigate the consequence of this phase transition on transport. We particularly consider a triple quantum dot system (three quantum dots sitting on the corners of an equilateral triangle) coupled to three leads symmetrically. To probe quantum phase transition we utilize slave-boson mean-field theory and to investigate transport properties we use scattering formalism. We detect a competition between Kondo and non-Kondo regime in this system. This competition affects transport in a way that conductance and noise will become zero when the non-Kondo regime dominates, in other words when the system crosses the phase boundaries. The results of this research can motivate experiments on the same systems to probe quantum phase transition and provides theoretical background for the experiment. It can also motivate future theoretical work using different methods from mean-field theory

Equity of colorectal cancer screening: which groups have inequitable participation and what can we do about it?

The National Bowel Cancer Screening Program (NBCSP) offers population-based screening for colorectal cancer (CRC) across Australia. The aims of this paper were to highlight the inequities in CRC screening in South Australia (SA) and the system-related barriers and enablers to CRC screening from the perspective of participants identified as having inequitable participation. First, de-identified data for the SA population of the NBCSP were statistically analysed and then mapped. Second, 117 in-depth interviews were conducted with culturally and linguistically diverse (CALD) groups, Indigenous and Anglo-Saxon Australians. Participation rates in the NBCSP were geographically and statistically significantly different (P < 0.0001) on the basis of gender (higher for women), age (higher for older people) and socioeconomic status (higher for more affluent people). The main system-related barriers were the lack of awareness of CRC or CRC screening within these groups, the problems with language due to most of the information being in English and the lack of recommendation by a doctor. This study revealed that inequity exists in the NBCSP participation in SA, and we identified both barriers and facilitators to CRC screening that require action at the level of both policy and practice. There is a large role in primary health care of both recommending CRC screening and facilitating equitable participation

Analysis of breastfeeding policies and practices in childcare centres in Adelaide, South Australia

Author version made available in accordance with publisher policy.Breastfeeding policies and practices were analysed in childcare settings in the metropolitan area of Adelaide, South Australia. Childcare centres were purposively selected based on their geographical location, type and socioeconomic score of the area. Qualitative inquiry approach was employed by undertaking interviews with childcare centres’ director or baby house coordinator to explore their perception towards breastfeeding practice and support within their centre. Breastfeeding related policy documents, where available, were also collected during the interviews to triangulate data. A total of 15 face-to-face interviews were conducted. Six childcare centres had a written policy specifically on breastfeeding support, although the technical issues of handling breastmilk were included in most centres’ food and nutrition guidelines. Most participants believed that decision to breastfeed is the personal choice of parents, and hence saw the childcare centre’s role as supporting parental choice whether it is breastfeeding or not. The provision of physical space to breastfeed and facilities to store the expressed breast milk were the most common practices in support of parents who had chosen to continue breastfeeding. Participants perceived mothers’ work-related issues such as distance from the centre, time, and unsupportive workplace the most important barriers that led to early introduction of bottle feeding or breastfeeding cessation. Most childcare centres support breastfeeding in a more passive than active way. Breastfeeding promotion needs to be an integral part of childcare centres training, policy and practice if an increased rate of breastfeeding is to be achieved particularly amongst working mothers.This work was made possible by a grant from the Faculty of Health Science, Flinders University

Addressing social determinants of health inequities through settings: a rapid review

Author version made available here in accordance with the publisher's policy.Changing settings to be more supportive of health and healthy choices is an optimum way to improve population health and health inequities. This paper uses the World Health Organisation’s (1998) definition of settings approaches to health promotion as those focused on modifying settings' structure and nature. A rapid literature review was undertaken in the period June-August 2014, combining a systematically conducted search of two major databases with targeted searches. The review focused on identifying what works in settings approaches to address the social determinants of health inequities, using Fair Foundations: the VicHealth framework for health equity (VicHealth 2013). This depicts the social determinants of health inequities as three layers of influence, and entry points for action to promote health equity. The evidence review identified work in twelve settings (cities; communities and neighbourhoods; educational; healthcare; online; faith-based; sports; workplaces; prisons; and nightlife, green and temporary settings), and work at the socioeconomic, political and cultural context layer of the Fair Foundations framework (governance, legislation, regulation and policy). It located a relatively small amount of evidence that settings themselves are being changed in ways which address the social determinants of health inequities. Rather, many initiatives focus on individual behaviour change within settings. There is considerable potential for health promotion professionals to focus settings work more upstream and so replace or integrate individual approaches with those addressing daily living conditions and higher level structures, and a significant need for programs to be evaluated for differential equity impacts and published to provide a more solid evidence base.This work was supported by the Victorian Health Promotion Foundation (VicHealth)

Cultural respect strategies in Australian Aboriginal primary health care services: beyond education and training of practitioners

This is the accepted version of the following article: [Freeman, T., Edwards, T., Baum, F., Lawless, A., Jolley, G., Javanparast, S. and Francis, T. (2014), Cultural respect strategies in Australian Aboriginal primary health care services: beyond education and training of practitioners. Australian and New Zealand Journal of Public Health, 38: 355–361. ], which has been published in final form at doi: 10.1111/1753-6405.12231. This item was under embargo for a period of 12 months from the date of publication, in accordance with the publisher's policy.Objective. There is little literature on health service level strategies for culturally respectful care to Aboriginal and Torres Strait Islander Australians. We conducted two case studies: , one Aboriginal community controlled, and one state government managed primary health care service to examine cultural respect strategies, client experiences, and barriers to cultural respect. Methods. Data were drawn from 22 interviews with staff from both services, and four community assessment workshops, with a total of 21 clients. Results. Staff and clients at both services reported positive appraisals of the achievement of cultural respects. Strategies included being grounded in a social view of health, including advocacy and addressing social determinants, employing Aboriginal staff, creating a welcoming service, supporting access through transport, outreach, and walk-in centres, and integrating cultural protocol. Barriers included communication difficulties, racism and discrimination, and externally developed programs. Conclusions. Service level strategies were necessary to achieving cultural respect. These strategies have the potential to improve Aboriginal and Torres Strait Islander health and wellbeing. Implications. Primary health care’s social determinants of health mandate, the community controlled model, and the development of the Aboriginal and Torres Strait Islander health workforce need to be supported to ensure a culturally respectful health system

Health system barriers influencing perinatal survival in mountain villages of Nepal: implications for future policies and practices

Background: This paper aims to examine the health care contexts shaping perinatal survival in remote mountain villages of Nepal. Health care is provided through health services to a primary health care level\u2014comprising district hospital, village health facilities and community-based health services. The paper discusses the implications for future policies and practice to improve health access and outcomes related to perinatal health. The study was conducted in two remote mountain villages in one of the most remote and disadvantaged mountain districts of Nepal. The district is reported to rank as the country\u2019s lowest on the Human Development Index and to have the worst child survival rates. The two villages provided a diversity of socio-cultural and health service contexts within a highly disadvantaged region. Methods: The study findings are based on a qualitative study of 42 interviews with women and their families who had experienced perinatal deaths. These interviews were supplemented with 20 interviews with health service providers, female health volunteers, local stakeholders, traditional healers and other support staff. The data were analysed by employing an inductive thematic analysis technique. Results: Three key themes emerged from the study related to health care delivery contexts: (1) Primary health care approach: low focus on engagement and empowerment; (2) Quality of care: poor acceptance, feeling unsafe and uncomfortable in health facilities; and (3) Health governance: failures in delivering health services during pregnancy and childbirth. Conclusions: The continuing high perinatal mortality rates in the mountains of Nepal are not being addressed due to declining standards in the primary health care approach, health providers\u2019 professional misbehaviour, local health governance failures, and the lack of cultural acceptance of formalised care by the local communities. In order to further accelerate perinatal survival in the region, policy makers and programme implementers need to immediately address these contextual factors at local health service delivery points