Vasodilator mechanisms in the dorsal aorta of the giant shovelnose ray, Rhinobatus typus (Rajiformes; Rhinobatidae)

This study investigated the nature of previous termvasodilator mechanismsnext term in the dorsal aorta of the giant shovelnose ray, Rhinobatus typus. Anatomical techniques found no evidence for an endothelial nitric oxide synthase, but neural nitric oxide synthase was found to be present in the perivascular nerve fibres of the dorsal aorta and other arteries and veins using both NADPH-diaphorase staining and immunohistochemistry with a specific neural NOS antibody. Arteries and veins both contained large nNOS-positive nerve trunks from which smaller nNOS-positive bundles branched and formed a plexus in the vessel wall. Single, varicose nNOS-positive nerve fibres were present in both arteries and veins. Within the large bundles of both arteries and veins, groups of nNOS-positive cell bodies forming microganglia were observed. Double-labelling immunohistochemistry using an antibody to tyrosine hydroxylase showed that nearly all the NOS nerves were not sympathetic. Acetylcholine always caused constriction of isolated rings of the dorsal aorta and the nitric oxide donor, sodium nitroprusside, did not mediate any dilation. Addition of nicotine (3×10−4 M) to preconstricted rings caused a vasodilation that was not affected by the nitric oxide synthase inhibitor, Image -NNA (10−4 M), nor the soluble guanylyl cyclase inhibitor, ODQ (10−5 M). This nicotine-mediated vasodilation was, therefore, not due to the synthesis and release of NO. Disruption of the endothelium significantly reduced or eliminated the nicotine-mediated vasodilation. In addition, indomethacin (10−5 M), an inhibitor of cyclooxygenases, significantly increased the time period to maximal dilation and reduced, but did not completely inhibit the nicotine-mediated vasodilation. These data support the hypothesis that a prostaglandin is released from the vascular endothelium of a batoid ray, as has been described previously in other groups of fishes. The function of the nitrergic innervation of the blood vessels is not known because nitric oxide does not appear to regulate vascular tone.

Strain rate effects on the energy absorption of rapidly manufactured composite tubes

Quasi-static and intermediate rate axial crush tests were conducted on tubular specimens of Carbon/Epoxy (Toray T700/G83C) and Glass/Polypropylene (Twintex). The quasi-static tests were conducted at 10 mm/min (1.67 x 10¯⁴ m/s); five different crush initiators were used. Tests at intermediate rates were performed at speeds of 0.25, 0.5, 0.75, 1, 2, and 4m/s. Modes of failure and specific energy absorption (SEA) values were studied. The highest SEA measured was 86 kJ/kg. This value was observed using Carbon/Epoxy samples at quasi static rates with a 45° chamfer initiator. The highest energy absorption for Twintex tubes was observed to be 57.56 kJ/kg during 45° chamfer initiated tests at 0.25 m/s. Compared with steel and aluminium, SEA values of 15 and 30 kJ/kg, respectively, the benefits of using composite materials in crash structures become apparent.

The Sawankhalok ceramic industry

A techno-historical study of a commercial initiative by 13th century Thai village potters to produce domestic stoneware ceramics. However their enterprise's success attracted the exploitative interest of regional trade entrepreneurs whose specialisation of the industry created a fatal lack of efficiency and flexibility.

Learning approaches and student perceptions of teaching quality

This research investigated the links between students' personal characteristics, their approaches to learning and their perceptions of teaching quality in a first-year accounting unit. Significant learning differences were found between Australian and Chinese students, and strong inter-relationships between contextual factors, such as teaching quality, and learning approaches were identified.

Reproduction, resistance and transformation at Marantha High School

The focus of this thesis is the attempt by the Seventh-day Adventist Church to reproduce SDA culture in students attending one of its schools, Maranatha High School. As a 'critical ethnography', it adopts a theoretical perspective from critical social theory to examine problems associated with this attempt. These problems are reflected in data gathered by a range of ethnographic techniques. The study first portrays the socio-political dynamics underlying the historical creation of Adventist culture generally, its embodiment in institutional forms, and the development of a substantial educational structure intended to transmit that culture to succeeding generations.

The study then focuses on current SDA educational philosophy, and the assumptions underlying the principles of selection, organisation, transmission and evaluation of knowledge considered to be valid. It then examines how Maranatha High School itself seeks to implement those principles. In this context, the study also reflects on the political implications of the modes of management and institutional control adopted at various levels of the organisation and in the school.

As a dialectical study, the thesis views the school as a social setting in which knowledgeable humans engage in communicative interaction. Rather than promoting smooth reproduction, the school is portrayed as a site of struggle, negotiation and potential transformation as participants resist forces that they perceive to be constraining and oppressing them. Consequently the thesis examines the perceptions of the various groups of participants, and the nature and impact of their interaction. In as much as teachers are official 'managers' of SDA culture and knowledge, this examination focuses especially on their personal definitions of the situation, the dilemmas that confront them from internal and external sources, the development of their own cultural forms in response, and the implications this action has for cultural reproduction and continuity.

Entrepreneurship : theory, process, practice

Covering foundations of entrepreneurship and new venture creation for the Asia-Pacific entrepreneur, this book combines a solid theoretical foundation with a practical step-by-step approach to the process of entrepreneurship.

Conductivity percolation in polyiodide/polymer complexes

Variable-temperature four-probe conductivity measurements and Raman spectroscopy were investigated for iodine in poly(propylene oxide) (PPO) and NaI₃ in PPO. The Raman spectra indicate the presence of both triiodide and polyiodide species in samples of I₂-doped PPO. The conductivity of these PPO/I₂ samples increased with increasing I₂ concentration and reached a plateau at approximately 12 vol % iodine. Raman spectra at 20 °C indicate that, at concentrations less than 23 vol % I₃-, the dominant species is the triiodide. Polymer salt complexes with varying amounts of I₃- appear to display a conductivity threshold near T_g, at 0.2 vol fraction of triiodide.

Perceptions of representatives of public, private, and community sector institutions of the barriers and enablers for physically active transport

Active transport bridges many shared concerns in the public health and transport sectors. To positively affect opportunities for active transport, public health and transport professionals are engaging with other sectors, including urban planning, housing, recreation, retail, education, and employer groups. A first step in such inter-sectoral collaboration is to understand the perceptions of key players in all of these sectors. This paper describes the results of structured interviews with senior and middle-level administrators from public, private, and community groups in a rapidly developing region in Queensland, Australia, to assess the perceived barriers and enablers to active transport. Key themes emerged relating to infrastructure delivery, public transport services, walk- and cycle-friendly community attributes, political leadership and government coordination, and societal travel norms and culture. There were also themes relating to limits due to resources and limited relevant technical expertise, institutional and practitioner cultures, and agencies not identifying with their roles in active transport. Policies and cross-government initiatives were seen to hold promise, including economic incentives and built environment guidelines, campaigns targeting public attitudes and opinions, and community participation in policy-making. These elements are potential keys to positively promoting comprehensive active transport initiatives among gatekeepers and leaders across different sectors.

Entrepreneurship : theory, process, practice

The theoretical foundation, overall structure and teaching elements of the US text have been retained, yet a high proportion of material has been updated to describe the Asia Pacific business environment. The text maintains a balance between regional examples and a global focus.

Immune-mediated mechanisms of parasite tissue sequestration during experimental cerebral malaria

Cerebral malaria is a severe complication of malaria. Sequestration of parasitized RBCs in brain microvasculature is associated with disease pathogenesis, but our understanding of this process is incomplete. In this study, we examined parasite tissue sequestration in an experimental model of cerebral malaria (ECM). We show that a rapid increase in parasite biomass is strongly associated with the induction of ECM, mediated by IFN-γ and lymphotoxin α, whereas TNF and IL-10 limit this process. Crucially, we discovered that host CD4+ and CD8+ T cells promote parasite accumulation in vital organs, including the brain. Modulation of CD4+ T cell responses by helminth coinfection amplified CD4+ T cell-mediated parasite sequestration, whereas vaccination could generate CD4+ T cells that reduced parasite biomass and prevented ECM. These findings provide novel insights into immune-mediated mechanisms of ECM pathogenesis and highlight the potential of T cells to both prevent and promote infectious diseases.

An analysis of police officers decisions about whether to refer cases of child abuse for prosecution

In many jurisdictions, police officers are responsible for deciding whether cases of child abuse are referred for potential prosecution. Such discretion justifies the need to scrutinise these professionals' decisions to determine if they are consistent with the scientific eyewitness memory literature. Prior research has shown that interviewer questioning is one of the most critical factors impacting the reliability of child witness statements. Hence, we asked: 'To what degree do officers' consider the quality of interviewer questions when making case authorisation decisions?'. In order to answer this question, we conducted a thematic analysis to identify issues referred to in a sample of documented police correspondence (n=33) about potential prosecution of child abuse cases. Two key themes emerged: the existence of corroborative evidence and whether the suspect denied the allegations. Questioning technique, however, was not considered. All but one decision that referred to interview process focused on the presentation of the witness, even though the witness interviews (as a whole) did not adhere to recommended best-practice guidelines. The implications of these findings are discussed.

Mental reinstatement of context with child witnesses : does it matter whether context is reinstated 'out loud'?

In this study we examined the impact of two types of mental reinstatement of context instructions in facilitating children's recall of a staged event across two stages of development. Specifically, a 2 times 3 factorial design was utilised incorporating two age groups (6- and 12-year-olds) and three interview conditions (standard recall, mental reinstatement where the child was instructed to reinstate the context 'out loud', and mental reinstatement without the explicit 'out loud' instruction). Overall, mental reinstatement instruction led to more correct and fewer incorrect responses than the standard recall instruction. The effect of mental reinstatement was similar across the age groups and irrespective of whether the child was asked to reinstate 'out loud'. Beneficial effects of the technique, however, were only evident for cued-recall questions as opposed to free-narrative responses. The implications of these findings and directions for future research are discussed.

The attractive female body weight and female body dissatisfaction in 26 countries across 10 world regions : results of the international body project 1

This study reports results from the first International Body Project (IBP-I), which surveyed 7,434 individuals in 10 major world regions about body weight ideals and body dissatisfaction. Participants completed the female Contour Drawing Figure Rating Scale (CDFRS) and self-reported their exposure to Western and local media. Results indicated there were significant cross-regional differences in the ideal female figure and body dissatisfaction, but effect sizes were small across highsocioeconomic-status (SES) sites. Within cultures, heavier bodies were preferred in low-SES sites compared to high-SES sites in Malaysia and South Africa (ds = 1.94-2.49) but not in Austria. Participant age, body mass index (BMI), and Western media exposure predicted body weight ideals. BMI and Western media exposure predicted body dissatisfaction among women. Our results show that body dissatisfaction and desire for thinness is commonplace in high-SES settings across world regions, highlighting the need for international attention to this problem.

Daring to Care : is spirituality sustainable in organizations providing healthcare?

Healthcare workers are challenged to dare to care enough to provide a service that is holistic. This involves being in tune with their own spirituality and the spiritual needs of their patients or clients. Spirituality and compassion are important concepts in the ministry of nurses and other health professionals. Compassion also has links with mercy, although there is debate as to whether mercy is the same as compassion for deserving or undeserving sufferers. However, healthcare workers need to care for sufferers even if their suffering is not deserved, where such compassion is intrinsic and/or out of duty. It involves acting altruistically. Faith-based organizations are best equipped to undertake this holistic ministry but as they are becoming increasingly reliant on government funding to help finance expensive health services they encounter rationalistic pressures from these funding sources may restrict the way they deliver these services. Decision and policymakers are encouraged to embrace altruistic values rather than the egoistic values of economic rationalism, not least because the nature of healthcare has an inherent emphasis on altruistic emotions, especially compassion.

Mechanisms of nitric oxide-mediated neurogenic,vasodilation in mesenteric resistance arteries of toad, Bufo marinus

This study determined the role of nitric oxide (NO) in neurogenic vasodilation in mesenteric resistance arteries of the toad Bufo marinus. NO synthase (NOS) was anatomically demonstrated in perivascular nerves, but not in the endothelium. ACh and nicotine caused TTX-sensitive neurogenic vasodilation of mesenteric arteries. The ACh-induced vasodilation was endothelium-independent and was mediated by the NO/soluble guanylyl cyclase signaling pathway, inasmuch as the vasodilation was blocked by the soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one and the NOS inhibitors N^ω- nitro-L-arginine methyl ester and N^ω-nitro-L-arginine. Furthermore, the ACh-induced vasodilation was significantly decreased by the more selective neural NOS inhibitor N⁵-(1-imino-3-butenyl)-L-ornithine. The nicotine-induced vasodilation was endothelium-independent and mediated by NO and calcitonin gene-related peptide (CGRP), inasmuch as pretreatment of mesenteric arteries with a combination of N^ω-nitro-L-arginine and the CGRP receptor antagonist CGRP-(8–37) blocked the vasodilation. Clotrimazole significantly decreased the ACh-induced response, providing evidence that a component of the NO vasodilation involved Ca^2+-activated K⁺ or voltage-gated K⁺ channels. These data show that NO control of mesenteric resistance arteries of toad is provided by nitrergic nerves, rather than the endothelium, and implicate NO as a potentially important regulator of gut blood flow and peripheral blood pressure.