Queer contingencies: bifurcation and the sexuality of schooling

This article critiques the contemporary focus on same-sex attracted youth, “antihomophobia,” and “safe schools,” as well as the ways these foci structure the logics of the prevailing policy approach. The author examines how contemporary antihomophobic reform in education is sustained by a series of false dilemmas: that the political demands and  investments of straights and nonstraights can be easily distinguished one from another; that the expression of homophobia is anathema to queer educative work; and that everything that is at stake in the messy confluence of sexuality, gender, and schooling can be made sense of by figuring the problem as a matter of being safe. Gesturing toward a queer social policy for schooling, this article critiques the “zero-tolerance” approach of antihomophobia education, arguing that it falsely bifurcates the social world of the school into homophobic/antihomophobic iterations, unsafe/safe versions, and straight/homosexual interest.

Diverse eukaryotes have retained mitochondrial homologues of the bacterial division protein FtsZ

Mitochondrial fission requires the division of both the inner and outer mitochondrial membranes. Dynamin-related proteins operate in division of the outer membrane of probably all mitochondria, and also that of chloroplasts – organelles that have a bacterial origin like mitochondria. How the inner mitochondrial membrane divides is less well established. Homologues of the major bacterial division protein, FtsZ, are known to reside inside mitochondria of the chromophyte alga Mallomonas, a red alga, and the slime mould Dictyostelium discoideum, where these proteins are likely to act in division of the organelle. Mitochondrial FtsZ is, however, absent from the genomes of higher eukaryotes (animals, fungi, and plants), even though FtsZs are known to be essential for the division of probably all chloroplasts. To begin to understand why higher eukaryotes have lost mitochondrial FtsZ, we have sampled various diverse protists to determine which groups have retained the gene. Database searches and degenerate PCR uncovered genes for likely mitochondrial FtsZs from the glaucocystophyte Cyanophora paradoxa, the oomycete Phytophthora infestans, two haptophyte algae, and two diatoms – one being Thalassiosira pseudonana, the draft genome of which is now available. From Thalassiosira we also identified two chloroplast FtsZs, one of which appears to be undergoing a C-terminal shortening that may be common to many organellar FtsZs. Our data indicate that many protists still employ the FtsZ-based ancestral mitochondrial division mechanism, and that mitochondrial FtsZ has been lost numerous times in the evolution of eukaryotes.

Apoptosis may underlie the pathology of zinc-deficient skin

The trace element zinc is essential for the survival and function of all cells. Zinc deficiency, whether nutritional or genetic, is fatal if left untreated. The effects of zinc deficiency are particularly obvious in the skin, seen as an erythematous rash, scaly plaques, and ulcers. Electron microscopy reveals degenerative changes within keratinocytes. Despite the well-documented association between zinc deficiency and skin pathology, it is not clear which cellular processes are most sensitive to zinc deficiency and could account for the typical pathological features. We used the cultured HaCaT keratinocyte line to obtain insight into the cellular effects of zinc deficiency, as these cells show many characteristics of normal skin keratinocytes. Zinc deficiency was induced by growing cells in the presence of the zinc chelator, TPEN, or by growth in zinc-deficient medium. Growth of cells in zinc-deficient medium resulted in a 44% reduction of intracellular zinc levels and a 75% reduction in the activity of the zinc-dependent enzyme, 5'-nucleotidase, relative to the control cells. Over a period of 7 days of exposure to zinc-deficient conditions, no changes in cell viability and growth, or in the cytoskeletal and cell adhesion systems, were found in HaCaT cells. At 7 days, however, induction of apoptosis was indicated by the presence of DNA fragmentation and expression of active caspase-3 in cells. These results demonstrate that apoptosis is the earliest detectable cellular change induced by zinc deficiency in HaCaT keratinocytes. Our observations account for many of the features of zinc deficiency, including the presence of degenerate nuclei, chromatin aggregates and abnormal organization of keratin, that may represent the later stages of apoptosis. In summary, a major causal role for apoptosis in the pathology of zinc deficiency in the skin is proposed. This role is consistent with the previously unexplained diverse range of degenerative cellular changes seen at the ultrastructural level in zinc-deficient keratinocytes.

Spherical indentation of superelastic shape memory alloys

Spherical indentation of superelastic shape memory alloys (SMAs) has been theoretically analyzed. Two characteristic points on the superelastic indentation curve have been discovered. The bifurcation force corresponding to the bifurcation point relies on the forward transformation stress and the return force corresponding to the return point relies on the reverse transformation stress.
Based on these theoretical relationships, an approach to determine the transformation stresses of superelastic SMAs has been proposed. To improve the accuracy of the measurement, a slope method to locate the two characteristic points from the slope curves is further suggested. Additionally, the spherical indentation hardness was also analyzed.

Analysis of spherical indentation of superelastic shape memory alloys

Dimensional analysis and the finite element method are applied in this paper to study spherical indentation of superelastic shape memory alloys. The scaling relationships derived from dimensional analysis bridge the indentation response and the mechanical properties of a superelastic shape memory alloy. Several key variables of a superelastic indentation curve are revealed and examined. We prove that the bifurcation force in a superelastic indentation curve only relies on the forward transformation stress and the elastic properties of the initial austenite; and the return force in a superelastic indentation curve only relies on the reverse transformation stress and the elastic properties of the initial austenite. Furthermore, the dimensionless functions to determine the bifurcation force and the return force are proved to be identical. These results not only enhance our understanding of spherical indentation of superelastic shape memory alloys, but also provide the theoretical basis for developing a practicable method to calibrate the mechanical properties of a superelastic material from the spherical indentation test.

The health equity dimensions of urban food systems

There is increasing recognition that the nutrition transition sweeping the world’s cities is multifaceted. Urban food and nutrition systems are beginning to share similar features, including an increase in dietary diversity, a convergence toward “Western-style” diets rich in fat and refined carbohydrate and within-country bifurcation of food supplies and dietary conventions. Unequal access to the available dietary diversity, calories, and gastronomically satisfying eating experience leads to nutritional inequalities and diet-related health inequities in rich and poor cities alike. Understanding the determinants of inequalities in food security and nutritional quality is a precondition for developing preventive policy responses. Finding common solutions to under- and overnutrition is required, the first step of which is poverty eradication through creating livelihood strategies. In many cities, thousands of positions of paid employment could be created through the establishment of sustainable and self-sufficient local food systems, including urban agriculture and food processing initiatives, food distribution centers, healthy food market services, and urban planning that provides for multiple modes of transport to food outlets. Greater engagement with the food supply may dispel many of the food anxieties affluent consumers are experiencing.

Editorial

When The Who sang about teenage angst in the 60s, their rock anthem ‘Talking about my Generation’ captured the divide between youth and beyond. Today, another divide – the digital divide – speaks to the issues of access, capital, and input that follow digital technologies. Like the earlier ‘me generation’, the new millennium D(igital) generation remains enigmatic, its members variously praised for their technological wizardry, criticised for their self-absorption, and pathologised for their unsociability. The D generation does not comprise youth alone, but the young are more exposed than others to the influence of new media and digital technologies. And like previous youth generations, they are often viewed as degenerate. A cybernetic degeneration symbolising society’s fears and cultural anxieties concerning the dehumanising prospects of technology appears most vividly in arguments about youth (Green & Bigum’s ‘aliens in the classroom’ [1993] is an apt description in this respect). Such negative rhetoric presents a dystopic view that tempers the more utopian, but equally reductionist visions of new technologies.

Studies on physiologic specialisation of albugo candida causing white blister on broccoli in Victoria

White blister caused by oomycete Albugo candida (Pers. Ex. Lev.) Kuntze, (AC), is an important disease affecting many cruciferous hosts, including vegetable brassicas. The outbreaks of white blister in broccoli and cauliflower crops (Brassica oleracea var. italica and var. botrytis) in Southern Australia in the last three years led to restrictions on movement of fresh produce and seedlings from the disease-affected areas. Current classification of AC races is based on physiologic specialisation of this pathogen. Race 9 has been identified to cause white blister on B. oleracea in the USA. We report on specialisation of AC causing disease in Victorian broccoli crops and the use of molecular tools for the separation of AC races. In a glasshouse, 12 Brassicaceae species/varieties replicated 6 times, were inoculated twice at the fully developed cotyledon stage with a distilled water suspension of zoosporangia (1x104 per ml) collected from a single broccoli leaf. Two weeks after inoculation the incidence of white blister on cotyledons and seedling leaves of cauliflower, broccoli, black mustard and Indian mustard was 79.7, 78.4, 73.7 and 6.9% respectively. Cabbage plants were symptomless indicating that further specialisation of the pathogen may have occurred in Australia. High disease incidence among black mustard plants shows that the Australian isolate differs from overseas AC race 9. The interaction of a number of B. oleracea varieties to a range of AC isolates from various hosts will be investigated. Degenerate primers are now being used to amplify actin and β-tubulin genes to identify race specific polymorphisms in AC isolates from three different hosts (wild radish, Chinese cabbage, and broccoli). Differing PCR amplification efficiencies from broccoli and wild radish isolates using degenerate actin primers indicates sequence differences in the two isolates. The fragments are now being cloned and sequenced for race comparison.

Chaos rules : an exploration of the work of instructional designers in distance education

This thesis provides an examination of the work of instructional designers in distance education, through the conceptual lens of chaos theory. Chaos theory was chosen as an analytical tool because of its ability to reveal the patterns and processes of complex systems as they move between order and turbulence. Recent work in the social sciences, specifically literary theory, has provided impetus for applications of chaos theory to educational settings. Specifically, chaos theory is used to analyse eight case studies of projects volunteered by instructional designers working in five institutions in Hong Kong and Australia. Data were gathered over a period of months with each participant, chiefly through interviews, but also involving diary accounts, electronic mail and letters. The methodology was thus qualitative, specifically informed by Eisner's vision of the ‘critical connoisseur’. Eisner equates an ‘enlightened eye’ with attainment of the skills of a critical connoisseur. First, an effective qualitative researcher must develop connoisseurship, the art of appreciation. On its own, though, connoisseurship is not enough; it is a private act, and thus needs a public face or presence. Criticism is this link, criticism being the art of disclosure. The critical connoisseur aims to help others to increase perception and deepen understanding of an educational situation or event. In addition to the empirical work, a parallel strand of this thesis investigates the theory and reported practice of instructional design. A brief history of instructional design is presented, along with discussion of acknowledged deficiencies of current theory and approaches. Recent reported investigations of both theory and practice are analysed from the viewpoint of chaos theory. Examination of key contributions in the literature of instructional design and distance education reveals considerable resonance between these contributions and the fundamental properties of chaotic systems. Links are made, in both the theoretical and empirical strands, between instructional design and the behaviour of dissipative structures, attractors and the process of bifurcation. Use is also made of the time-dependent nature of chaos theory as a theory of becoming, rather than one of being. The thesis comprises eight chapters, two appendices and a references section. The introductory chapter explains the research problem, and outlines the structure of the thesis. Methodological considerations are left until after an assessment of instructional design literature and (reported) practice. This deliberately theoretical investigation (Chapters 2 and 3) comprises the first of the parallel strands that are presented. The basic conclusions are that instructional design theory has not been particularly helpful to or used by instructional designers, and that chaos theory might provide an alternative way of viewing instructional design practice. The other parallel strand is the empirical work, which for four chapters outlines the methodology and my findings concerning the role of instructional designers in distance education. The methodology is detailed in Chapter 4. Chapter 5 establishes the contexts of the participants, by examining their backgrounds and introductions to their roles. It also investigates their views on their role and status within their institutions and with working colleagues. Chapter 6 is an exploration of the major issues that influenced the work of the instructional designers. These are the issues that arose naturally in the interviews as the participants outlined the development and interactions that took place on a day to day basis. Time emerges as a key influence in their work, and its effects on the projects are outlined and analysed. The ways that instructional designers give advice to those with whom they work is also investigated. The next chapter continues consideration of their work, but this time as they reflect on their role and its demands. This includes their reactions to the various metaphors that have appeared in the literature, along with those that they introduced into our discussions. The links that are established between the two parallel strands are drawn more explicitly in the final chapter, Chapter 8, which is a notion of what a model of instructional design based on my conclusions might resemble. It summarises the evidence that it is not necessarily by striving for order—in fact quite the opposite — during key periods of course development, that leads to creative outcomes. The introduction of uncertainty and turbulence does, in some cases and under some conditions, move the system to a higher level. The image that is offered from chaos theory is that of time-bound dissipative structures, interacting with their open environment at far-from-equilibrium conditions, and transforming themselves from disorder to order through bifurcation. The role of strange or chaotic attractors is highlighted in the process. The first appendix gives background information in terms of the methodology. The second is the heart of the data upon which the thesis draws. That is, the second appendix outlines the case studies of the participants. Most are short summaries, but the final one is a detailed study, tracing the progress of the design and development of a subject in distance education.

Understanding the concept of elasticity in supply chain relationships : an agency theory perspective

The issue of flexibility in supply chains has been receiving heightened attention by scholars and practitioners especially as business environment becoming more turbulent and uncertain. Notwithstanding, one of the important aspects of flexibility – relationship flexibility – which has the potential to proliferate responsiveness and postpone bifurcation in buyer -supplier relationships has not been well understood and researched. Identifying this gap within the literature, this paper proposes a concept of elasticity as an important element of relationship flexibility in supply chains. It is argued that the tolerance threshold of coopering parties in presence of their sudden behaviour change will determine their state of relationship elasticity (i.e. elastic or inelastic). The theoretical development of this paper has been primarily based on review of the literature and insights from agency perspective. It is proposed that relationship governance mechanisms advocated by agency theory has the potential to influence elasticity status of principal agent relationships.