Cough formation in viral infections in children

Using a multidisciplinary approach, Human Respiratory Viral Infections is set at the level between the definitive reference work and an essential clinical manual. Exploring recent advances in human respiratory viral research, the text builds on the basic sciences of epidemiology, virology, molecular biology, and immunology to cover clinical diagnosis, mechanism of pathogenesis, manifestations of disease, impact, treatment, and management strategies.

Putting vital stains in context

While vital staining remains a cornerstone in the diagnosis of ocular disease and contact lens complications, there are many misconceptions regarding the properties of commonly used dyes by eye-care practitioners and what is and what is not corneal staining after instillation of sodium fluorescein. Similarly, the proper use and diagnostic utility of rose Bengal and lissamine green B, the other two ophthalmic dyes commonly used for assessing ocular complications, have similarly remained unclear. Due to the limitations of vital stains for definitive diagnosis, concomitant signs and symptoms in addition to a complete patient history are required. Over the past decade, there have been many reports of a type of corneal staining—often referred to as solution-induced corneal staining (SICS)—that is observed with the use of multipurpose solutions in combination with soft lenses, more specifically silicone hydrogel lenses. Some authors believe that SICS is a sign of lens/solution incompatibility; however, new research shows that SICS may be neither a measure of lens/solution biocompatibility nor ‘true’ corneal staining, as that observed in pathological situations. A large component of SICS may be a benign phenomenon, known as preservative-associated transient hyperfluorescence (PATH). There is a lack of correlated signs and/or symptoms with SICS/PATH. Several properties of SICS/PATH, such as appearance and duration, differentiate it from pathological corneal staining. This paper reviews the properties of vital stains, their use and limitations in assessment of the ocular surface, the aetiology of corneal staining, characteristics of SICS/PATH that differentiate it from pathological corneal staining and what the SICS/PATH phenomenon means for contact lens-wearing patients.

Response to re : putting vital stains in context

A response to: "Re: Putting vital stains in context" by Eric Papas & Lyndon Jones, published in the same issue of this journal. "There has been considerable discussion in recent times about the origins of solution-induced corneal staining (SICS) and I welcome this opportunity to further clarify some points raised in my paper1 in relation to certain issues highlighted by Drs Papas and Jones.2 Part of the difficulty in understanding these phenomena relates to the imprecise terminology used. For example, Drs Papas and Jones state ‘. . . SICS..."

Response to re : putting vital stains in context

A response to "Re: Putting vital stains in context" by Charles W McMonnies, published in the same issue of this journal. "I thank Professor McMonnies for his thoughtful comments,1 which rightly forcemeto more directly address the clinical ramifications of solution-induced corneal staining (SICS). I concur with his observation that determining whether the staining can be attributed to preservative-associated transient hyperfluorescence (PATH) or true pathology can be difficult in a typical clinical situation, perhaps requiring two visits in a single day. There is no easy answer to this dilemma..."

Hydroxyl radical formation in the gas phase oxidation of distonic 2-methylphenyl radical cations

The reactions of distonic 4-(N, N, N-trimethylammonium)-2-methylphenyl and 5-(N, N, N-trimethylammonium)-2-methylphenyl radical cations (m/z 149) with O-2 are studied in the gas phase using ion-trap mass spectrometry. Photodissociation (PD) of halogenated precursors gives rise to the target distonic charge-tagged methylphenyl radical whereas collision-induced dissociation (CID) is found to produce unreactive radical ions. The PD generated distonic radicals, however, react rapidly with O-2 to form \[M + O2](center dot+) and \[M + O-2 - OH](center dot+) ions, detected at m/z 181 and m/z 164, respectively. Quantum chemical calculations using G3SX(MP3) and M06-2X theories are deployed to examine key decomposition pathways of the 5-(N, N, N-trimethylammonium)-2-methylphenylperoxyl radical and rationalise the observed product ions. The prevailing product mechanism involves a 1,5- H shift in the peroxyl radical forming a QOOH-type intermediate that subsequently eliminates (OH)-O-center dot to yield charge-tagged 2-quinone methide. Our study suggests that the analogous process should occur for the neutral methylphenyl + O-2 reaction, thus serving as a plausible source of (OH)-O-center dot radicals in combustion environments. Grants: ARC/DP0986738, ARC/DP130100862

Mechanical influences on endothelial cell network formation in vitro

While both the restoration of the blood supply and an appropriate local mechanical environment are critical for uneventful bone healing, their influence on each other remains unclear. Human bone fracture haematomas (<72h post-trauma) were cultivated for 3 days in fibrin matrices, with or without cyclic compression. Conditioned medium from these cultures enhanced the formation of vessel-like networks by HMEC-1 cells, and mechanical loading further elevated it, without affecting the cells’ metabolic activity. While haematomas released the angiogenesis-regulators, VEGF and TGF-β1, their concentrations were not affected by mechanical loading. However, direct cyclic stretching of the HMEC-1 cells decreased network formation. The appearance of the networks and a trend towards elevated VEGF under strain suggested physical disruption rather than biochemical modulation as the responsible mechanism. Thus, early fracture haematomas and their mechanical loading increase the paracrine stimulation of endothelial organisation in vitro, but direct periodic strains may disrupt or impair vessel assembly in otherwise favourable conditions.

Mass spectrometric study of the dissociation of Group XI metal complexes with fatty acids and glycerolipids : Ag2H+ and Cu2H+ ion formation in the presence of a double bond

Results of mass spectrometric studies are reported for the collisional dissociation of Group XI (Cu, Ag, Au) metal ion complexes with fatty acids (palmitic, oleic, linoleic and a-linolenic) and glycerolipids. Remarkably, the formation of M2H+ ions (M = Cu, Ag) is observed as a dissociation product of the ion complexes containing more than one metal cation and only if the lipid in the complex contains a double bond. Ag2H+ is formed as the main dissociation channel for all three of the fatty acids containing double bonds that were investigated while Cu2H+ is formed with one of the fatty acids and, although abundant, is not the dominant dissociation channel. Also. Cu(I) and Ag(I) ion complexes were observed with glycerolipids (including triacylglycerols and glycerophospholipids) containing either saturated or unsaturated fatty acid substituents. Interestingly. Ag2H+ ion is formed in a major fragmentation channel with the lipids that are able to form the complex with two metal cations (triacylglycerols and glycerophosphoglycerols), while lipids containing a fixed positive charge (glycerophospocholines) complex only with a single metal cation. The formation of Ag2H+ ion is a significant dissociation channel from the complex ion Ag-2(L-H)(+) where L = Glycerophospholipid (GP) (18:1/18:1). Cu(I) also forms complexes of two metal cations with glycerophospholipids but these do not produce Cu2H+ upon dissociation. Rather organic fragments, not containing Cu(I), are formed, perhaps due to different interactions of these metal cations with lipids resulting from the much smaller ionic radius of Cu(I) compared to Ag(I) (C).

Policing in Context : An Introduction to Police Work in Australia

Policing in Context is a well structured introductory text that gives students the practical information they need to grasp the diverse roles, duties, powers and problems of policing in Australia. This book approaches policing in three key sections, creating a natural flow of information. The first section sets up the basic knowledge needed for understanding the history, context and structure of policing in Australia. The second section provides a description of the core skills, tasks and operations of police work. In the final section, chapters cover and reflect on contemporary and emerging issues.

Corner and finger formation in Hele-Shaw flow with kinetic undercooling regularisation

We examine the effect of a kinetic undercooling condition on the evolution of a free boundary in Hele--Shaw flow, in both bubble and channel geometries. We present analytical and numerical evidence that the bubble boundary is unstable and may develop one or more corners in finite time, for both expansion and contraction cases. This loss of regularity is interesting because it occurs regardless of whether the less viscous fluid is displacing the more viscous fluid, or vice versa. We show that small contracting bubbles are described to leading order by a well-studied geometric flow rule. Exact solutions to this asymptotic problem continue past the corner formation until the bubble contracts to a point as a slit in the limit. Lastly, we consider the evolving boundary with kinetic undercooling in a Saffman--Taylor channel geometry. The boundary may either form corners in finite time, or evolve to a single long finger travelling at constant speed, depending on the strength of kinetic undercooling. We demonstrate these two different behaviours numerically. For the travelling finger, we present results of a numerical solution method similar to that used to demonstrate the selection of discrete fingers by surface tension. With kinetic undercooling, a continuum of corner-free travelling fingers exists for any finger width above a critical value, which goes to zero as the kinetic undercooling vanishes. We have not been able to compute the discrete family of analytic solutions, predicted by previous asymptotic analysis, because the numerical scheme cannot distinguish between solutions characterised by analytic fingers and those which are corner-free but non-analytic.

Online Gaming in Context : the Social and Cultural Significance of Online Games

There is little question of the social, cultural and economic importance of video games in the world today, with gaming now rivalling the movie and music sectors as a major leisure industry and pastime. The significance of video games within our everyday lives has certainly been increased and shaped by new technologies and gaming patterns, including the rise of home-based games consoles, advances in mobile telephone technology, the rise in more 'sociable' forms of gaming, and of course the advent of the Internet. This book explores the opportunities, challenges and patterns of gameplay and sociality afforded by the Internet and online gaming. Bringing together a series of original essays from both leading and emerging academics in the field of game studies, many of which employ new empirical work and innovative theoretical approaches to gaming, this book considers key issues crucial to our understanding of online gaming and associated social relations, including: patterns of play, legal and copyright issues, player production, identity construction, gamer communities, communication, patterns of social exclusion and inclusion around religion, gender and disability, and future directions in online gaming.

Towards a quantitative theory of epidermal calcium profile formation in unwounded skin

We propose and mathematically examine a theory of calcium profile formation in unwounded mammalian epidermis based on: changes in keratinocyte proliferation, fluid and calcium exchange with the extracellular fluid during these cells' passage through the epidermal sublayers, and the barrier functions of both the stratum corneum and tight junctions localised in the stratum granulosum. Using this theory, we develop a mathematical model that predicts epidermal sublayer transit times, partitioning of the epidermal calcium gradient between intracellular and extracellular domains, and the permeability of the tight junction barrier to calcium ions. Comparison of our model's predictions of epidermal transit times with experimental data indicates that keratinocytes lose at least 87% of their volume during their disintegration to become corneocytes. Intracellular calcium is suggested as the main contributor to the epidermal calcium gradient, with its distribution actively regulated by a phenotypic switch in calcium exchange between keratinocytes and extracellular fluid present at the boundary between the stratum spinosum and the stratum granulosum. Formation of the extracellular calcium distribution, which rises in concentration through the stratum granulosum towards the skin surface, is attributed to a tight junction barrier in this sublayer possessing permeability to calcium ions that is less than 15 nm/s in human epidermis and less than 37 nm/s in murine epidermis. Future experimental work may refine the presented theory and reduce the mathematical uncertainty present in the model predictions.

A new period of volcanogenic massive sulfide formation in the Yilgarn: A volcanological study of the ca 2.76 Ga Hollandaire VMS deposit, Yilgarn Craton, Western Australia

The Archean Hollandaire volcanogenic massive sulfide deposit is a felsic–siliciclastic VMS deposit located in the Murchison Domain of the Youanmi Terrane, Yilgarn Craton, Western Australia. It is hosted in a succession of turbidites, mudstones and coherent rhyodacite sills and has been metamorphosed to upper greenschist/lower amphibolite facies and includes a pervasive S1 deformational fabric. The coherent rhyodacitic sills are interpreted as syndepositional based on geochemical similarities with well-known VMS-associated felsic rocks and similar foliations to the metasediments. We offer several explanations for the absence of textural evidence (e.g. breccias) for syn-depositional origins: 1) the subaqueous sediments were dehydrated by long-lived magmatism such that no pore-water remained to drive quench fragmentation; 2) pore-space occlusion by burial and/or, 3) alteration overprinting and obscuring of primary breccias at contact margins. Mineralisation occurs by sub-seafloor replacement of original host rocks in two ore bodies, Hollandaire Main (~125 x >500 m and ~8 m thick) and Hollandaire West (~100 x 470 m and ~5 m thick), and occurs in three main textural styles, massive sulfides, which are exclusively hosted in turbidites and mudstones, and stringer and disseminated sulfides, which are also hosted in coherent rhyodacite. Most sulfides have textures consistent with remobilisation and recrystallisation. Hydrothermal metamorphism has altered the hangingwall and footwall to similar degrees, with significant gains in Mg, Mn and K and losses in Na, Ca and Sr. Garnet and staurolite porphyryoblasts also exhibit a footprint around mineralisation, extending up to 30 m both above and below the ore zone. High precision thermal ionisation mass spectrometry of zircons extracted from the coherent rhyodacite yield an age of 2759.5 ± 0.9 Ma, which along with geochemical comparisons, places the succession within the 2760–2735 Ma Greensleeves Formation of the Polelle Group of the Murchison Supergroup. Geochemical and geochronological evidence link the coherent rhyodacite sills to the Peter Well Granodiorite pluton ~2 km to the W, which acted as the heat engine driving hydrothermal circulation during VMS mineralisation. This study highlights the importance of both: detailed physical volcanological studies from which an accurate assessment of timing relationships, particularly the possibility of intrusions dismembering ore horizons, can be made; and identifying synvolcanic plutons and other similar suites, for VMS exploration targets in the Youanmi Terrane and worldwide.

Dance teaching and learning in context : activating the head, heart and hands

Traditionally, the art of teaching dance has largely been a skill transferred from teacher to student. This master-apprentice paradigm encourages the passing on of technical and artistic traditions associated with the various genres of dance. Whilst this approach supports the passing of the flame of the art form from generation to generation, it has, in part, limited the teaching pedagogy that informs dance as an art form. The future of dance teaching is reliant on teachers’ engagement with the further development of inquiry learning and reflective practice skills within the dance studio. This paper charts one component of a reflective pedagogy, Head, Heart, Hands (Pstalozzi as cited in Rud 2006), developed as a result of an action research project, within a suite of three units across a three-year undergraduate teacher-training course for school, community and studio dance teachers.