Recent advances in chloroplast and mitochondrial division

Stomatin, originally identified as a major protein of the human erythrocyte membrane, is widely expressed in various tissues. Orthologues are found in vertebrates, invertebrates, plants, and microorganisms. Related proteins exhibit a common core structure, termed the prohibitin (PHB) domain, with varying extensions. Stomatin has an unusual topology, similar to caveolin-1, with a hydrophobic domain embedded at the cytoplasmic side of the membrane. Additional anchoring is provided by palmitoylation and the membrane affinity of the PHB domain. Stomatin associates with cholesterol-rich microdomains (lipid rafts), forms oligomers, and thereby displays a scaffolding function by generating large protein-lipid complexes. It regulates the activity of various membrane proteins by reversibly recruiting them to lipid rafts. This mechanism of regulation has been shown for GLUT-1 and may also apply for ion channels. Stomatin is located at the plasma membrane, particularly in microvilli, in endocytic and exocytic vesicles, and cytoplasmic granules. Stomatin-carrying endosomes are highly dynamic and interact with lipid droplets suggesting a role in intracellular lipid transport. This subcellular distribution and the caveolin-like protein structure suggest important membrane organizing functions for stomatin. A general picture emerges now that cell membranes contain cholesterol-rich domains that are generated and regulated by scaffolding proteins like caveolins, stomatins, and flotillin/reggie proteins.

Plastid division in mallomonas (Synurophyceae, Heterokonta)

Laser scanning confocal microscopy and TEM were used to study the morphology of secondary plastids in algae of the genus Mallomonas (Synurophyceae). At interphase, Mallomonas splendens (G. S. West) Playfair, M. rasilis Dürrschm., M. striata Asmund, and M. adamas K. Harris et W. H. Bradley contained a single H-shaped plastid consisting of two large lobes connected by a narrow isthmus. Labeling of DNA revealed a necklace-like arrangement of plastid nucleoids at the periphery of the M. splendens plastid and a less-patterned array in M. rasilis. The TEM of M. splendens and M. rasilis showed an electron-dense belt surrounding the plastid isthmus in interphase cells; this putative plastid-dividing ring (PD ring) was adpressed to the inner pair of the four plastid membranes, suggesting that it is homologous to the PD ring of green and red plastids. The PD ring did not contain actin (indicated by lack of staining with phalloidin) and displayed filaments or tubules of 5–10 nm in diameter that may be homologous to the tubules described in red algal PD rings. Confocal microscopy of chl autofluorescence from M. splendens showed that the plastid isthmus was severed as mitosis began, giving rise to two single-lobed daughter plastids, which, as mitosis and cell division progressed, separated from one another and then each constricted to form the H-shaped plastids of daughter cells. Similar plastid division cycles were observed in M. rasilis and M. adamas; however, the plastid isthmus of M. striata was retained throughout most of cell division and was eventually severed by the cell cleavage furrow.

Reflexivity: a concept and its meanings for practitioners working with children and families

Reflexivity is a concept that is increasingly gaining currency in professional practice literature, particularly in relation to working with uncertainty and as an important feature of professional discretion and ethical practice. This article discusses how practitioners working in child and family welfare/protection organisations understood and interpreted the concept of reflexivity for their practice, as one of the outcomes of larger, collaborative research project. This project was conducted through a series of workshops with practitioners. The overall research that aimed to expand practitioners’ practice repertoires from narrowly-defined risk assessment, to an approach that could account for the uncertainties of practice, included the concept of reflexivity as an alternative or a complement to instrumental accountability that is increasingly a feature in child welfare/protection organisations. This article discusses how the concept of reflexivity was explored in the research and how practitioners interpreted the concept for their practice. We conclude that while concepts like reflexivity are central to formal theories for professional practice, we also recognise that individual practitioners interpret concepts (in ways that are both practically and contextually relevant), thus creating practical meanings appropriate to their practice contexts.

Roman concept of mental capacity to make end-of-life decisions

When assessing decisional competence of patients, psychiatrists have to balance the patients' right to personal autonomy, their condition and wishes against principles of medical ethics and professional discretion. This article explores the age-old legal and ethical dilemmas posed by refusal of vital medical treatment by patients and their mental capacity to make end-of-life decisions against the background of philosophical, legal and medical approaches to these issues in the time of the Younger Pliny (c62–c113 CE). Classical Roman discourse regarding mental competency and "voluntary death" formed an important theme of the vast corpus of Greco-Roman writings, which was moulded not only by legal permissibility of suicide but also by philosophical (in modern terms, moral or ethical) considerations. Indeed, the legal and ethical issues of evaluating the acceptability of end of life decisions discussed in the Letters are as pertinent today as they were 2000 years ago. We may gain valuable insights about our own methodologies and frames of reference in this area of the law and psychiatry by examining Classical Roman approaches to evaluating acceptability of death-choices as described in Pliny's Letters and the writings of some of his peers.

Does the concept of ″altered states of consciousness″ rest on a mistake?

Block (2002) has argued that the multiplicity of meanings ascribed to consciousness is due to the erroneous treatment of very different concepts as a single concept. Block distinguished four notions of consciousness intended to encapsulate the various meanings attributed to the term: phenomenal, access, self, and monitoring consciousness. We argue that what is common to all of these definitions is the implicit distinction between consciousness and the content of consciousness. We critically examine the term “altered state of consciousness” and argue that affixing the qualifier “altered state” to consciousness results in a theoretical confusion of consciousness and its content, that is, consciousness is mistaken for the content of consciousness. We refer to this as the consciousness/content fallacy and argue that it may be avoided if one supplants “altered states of consciousness” with “altered pattern of phenomenal properties,” an extrapolation of the term “phenomenal field.” Implications of the consciousness/content fallacy for theory and research are also considered.

A proposed cyber-terroism SCADA risk framework concept for Australia

Terrorist groups are in theory currently using information and communication technologies (ICTs) to orchestrate their conventional attacks. More recently, terrorists have been developing a new form of capability within the cyber arena to coordinate cyber based attacks. This paper examines a proposed cyber-terrorism SCADA risk framework concept. The paper proposes a conceptual framework which is designed to measure and protect the threat of cyber-terrorism against SCADA systems within Australia. The findings and results of a focus group will be examined to help validate the framework concept.

The Permian-Triassic Boundary Stratigraphic Set: characteristics and correlation

Eased on field observations and compilation of data, a new stratigraphic concept, herein named the Permian-Triassic boundary stratigraphic set (PTBST), is proposed. The PTBST consists of, in ascending order, beds of claystone, limestone (or marl) and claystone. This boundary stratigraphic
set has been recognized at many sections in the Yangtze region of South China, with laterally stable lithological characters, the same or comparable biotas, comparable radiometric ages, and identical or similar magnetostratigraphic and chemostratigraphic signals. Therefore, the PTBST marks an isochronous unit and can serve as an important and effective marker set for regional and global correlations.
The important index fossils for the lowermost Triassic, Hindeodus parvus or Claraia, may be diachronous in their first occurrences with respect to the base of the PTBST and, therefore, should not be used as an exclusive indicator for the beginning of the Triassic. Rather more attention should
be paid to events, succession of events and/or event surfaces, which would potentially provide a more precise tool for high-resolution stratigraphic division and correlation.

Registered nurses` lived experience of advocacy within a critical care nuit: a phenomenological study

Anecdotally, it has often been expressed by registered nurses (RNs) working within critical care environments that they are patient advocates. However, to date, little systematic research has been undertaken to validate this assertion. Thus this project, which explored the lived experience of RNs working within a critical care unit in a country area of Australia, was conceived.

The five participants of this study were all Division 1 RNs possessing a critical care certificate and a minimum of 4 years' nursing experience. Through their participation in an in-depth audiotaped interview they revealed a wealth of experiences and ideas about their involvement as patient advocates. The results of this research indicate that the phenomenon of nurse advocacy is a multi-faceted process and embraces many kinds of activities that nurses engage in on behalf of their clients.

The findings of this study indicate that some of the participants' experiences are congruent with elements of advocacy contained within the nursing literature and statements of professional nursing bodies. However, there are some findings in this study that are not consistent with available literature. For instance, these participants markedly reject the notion that advocacy is an inappropriate concept for nurses, despite suggestions in the literature that this is an inappropriate role. Instead they wholeheartedly embrace this role, asserting it as central to their practice. Further, although the literature identifies potential controversies regarding enactment of the role of advocacy, the participants of this study are silent on these matters. It is not known what this silence implies and, in light of the study findings, it is recommended that nursing organisations, theorists and clinicians consider whether it is worthwhile to more clearly confirm the nature and role of advocacy within Australian nursing.

Mobile banking : concept and potential

The internet and the mobile phone - two technological advancements that have profoundly affected human behaviour in the last decade - have started to converge. The products .of this association are mobile data services. Using a variety of platforms, services are being created to enable mobile devices to perform many activities of the traditional internet, albeit in a reduced format for mobile devices. One area of activity is mobile (m-) banking (one of the first areas of commercial transaction on the wireless internet). Banking is an area that has extended in many different ways in recent years, including telephone and online banking. M-banking provides yet another channel for banking services, and in emerging markets, provides some possibility for becoming a primary channel. This paper examines the strategic implications of m-banking and the strategic positioning of m-banking services in different markets. The paper concludes with a discussion of the future for m-banking services.

Requirement for the cell division protein DivIB in polar cell division and engulfment during sporulation in Bacillus subtilis

During spore formation in Bacillus subtilis, cell division occurs at the cell pole and is believed to require essentially the same division machinery as vegetative division. Intriguingly, although the cell division protein DivIB is not required for vegetative division at low temperatures, it is essential for efficient sporulation under these conditions. We show here that at low temperatures in the absence of DivIB, formation of the polar septum during sporulation is delayed and less efficient. Furthermore, the polar septa that are complete are abnormally thick, containing more peptidoglycan than a normal polar septum. These results show that DivIB is specifically required for the efficient and correct formation of a polar septum. This suggests that DivIB is required for the modification of sporulation septal peptidoglycan, raising the possibility that DivIB either regulates hydrolysis of polar septal peptidoglycan or is a hydrolase itself. We also show that, despite the significant number of completed polar septa that form in this mutant, it is unable to undergo engulfment. Instead, hydrolysis of the peptidoglycan within the polar septum, which occurs during the early stages of engulfment, is incomplete, producing a similar phenotype to that of mutants defective in the production of sporulation-specific septal peptidoglycan hydrolases. We propose a role for DivIB in sporulation-specific peptidoglycan remodelling or its regulation during polar septation and engulfment.

Cause-related marketing : an extension of the congruity concept

This paper considers the concept of congruity or 'fit' in a cause-related marketing (CRM) context. At present, there is a gap in the literature that explores how nonprofit-forprofit pairings affect a consumer's response to and evaluation of CRM campaigns. This paper develops the concept of 'fit' with particular attention being paid to three dimensions, namely, cognitive, emotional and behavioural congruity and the role these concepts play in determining consumers’ perception of the 'relatedness' of products and causes.