From mass to structure: An aromaticity index for high-resolution mass data of natural organic matter

Recent progress in Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) provided extensive molecular mass data for complex natural organic matter (NOM). Structural information can be deduced solely from the molecular masses for ions with extreme molecular element ratios, in particular low H/C ratios, which are abundant in thermally altered NOM (e.g. black carbon). In this communication we propose a general aromaticity index (AI) and two threshold values as unequivocal criteria for the existence of either aromatic (AI > 0.5) or condensed aromatic structures (AI >= 0.67) in NOM. AI can be calculated from molecular formulae which are derived from exact molecular masses of naturally occurring compounds containing C, H, O, N, S and P and is especially applicable for substances with aromatic cores and few alkylations. In order to test the validity of our model index, AI is applied to FTICRMS data of a NOM deep-water sample from the Weddell Sea (Antarctica), a fulvic acid standard and an artificial dataset of all theoretically possible molecular formulae. For graphical evaluation a ternary plot is suggested for four-dimensional data representation. The proposed aromaticity index is a step towards structural identification of NOM and the molecular identification of black carbon in the environment

Developing site-specific guidelines for orchard soils based on bioaccessibility – Can it be done?

Horticultural land within the periurban fringe of NZ towns and cities increasingly is being developed for residential subdivision. Recent surveys have shown that concentrations of As, Cd, Cu, Pb, and ΣDDT (sum of DDT and its degradation products DDE and DDD) in such soils can exceed criteria protective of human health.¹ Soil ingestion is a key exposure pathway for non-volatile contaminants in soil. Currently in NZ, site-specific risk assessments and the derivation of soil guidelines protective of human health assume that all of the contaminant present in the soil is available for uptake and absorption by the human gastrointestinal tract. This assumption can overestimate health risks and has implications for the remediation of contaminated sites.² In comparison, the bioavailability of contaminants is considered when estimating exposure via dermal absorption and by ingestion of home-grown produce.³ Dermal absorption factors and plant uptake factors are included in the calculations for estimating exposures via these routes

Leaving Care: Unaccompanied AsylumSeeking Young Afghans Facing Return

Unaccompanied asylum-seeking children in the United Kingdom approach adulthood knowing that they will be encouraged or even forced to return to their countries of birth. Drawing on a project that promoted voluntary return to Afghanistan, we use interviews with twelve young people, professionals working in the Home Office and in education, local authorities, and voluntary-sector agencies to describe a complex area of immigration policy. We show how the state’s obligations as “corporate parent” clash with increasingly punitive migration controls and with growing political scrutiny of public spending. We propose education as a way to prepare young people for futures as global citizens in either country of settlement or of origin

Voices in Australia\u27s Aboriginal and Canada\u27s First Nations Literatures

Kim Scott suggests in his text I Come from Here by means of yarning that the authority of Indigenous people and language is primary to an authentic sense of place. Scott uses an accumulative, episodic, and personal narrative style to argue that the return to, and consolidation of cultural material in, a community of descendants of the informants must be founded upon principles of community development. Collaboration between Indigenous and non-Indigenous people by sharing of ancestral material with ever widening, concentric circles is how this process results in respect and partnership that empowers community life. Eden Robinson explores in her text 99.99% True & Authentic Tales with humor how the past and present coexist in contemporary Haisla life. In the process, Robinson also depicts some of the challenges faced by Canada\u27s First Nations writers, whose readers can become so determined to experience the culture represented to them that they wish to live not only in an author\u27s hometown but in her very home. In this way Robinson explores issues of voice, authenticity, and the process of making meaning: to whom does a story belong and who has the right to tell it? How can a story be told

Diagnosis of the significance of inconsistencies in software designs: a framework and its experimental evaluation

This paper presents: (a) a framework for assessing the significance of inconsistencies which arise in object-oriented design models that describe software systems from multiple perspectives, and (b) the findings of a series of experiments conducted to evaluate it. The framework allows the definition of significance criteria and measures the significance of inconsistencies as beliefs for the satisfiability of these criteria. The experiments conducted to evaluate it indicate that criteria definable in the framework have the power to create elaborate rankings of inconsistencies in models

Direction-dependent Optical Modes in Nanoscale Silicon Waveguides

On-chip photonic networks have the potential to transmit and route information more efficiently than electronic circuits. Recently, a number of silicon-based optical devices including modulators, buffers, and wavelength converts have been reported. However, a number of technical challenges need to be overcome before these devices can be combined into network-level architectures. In particular, due to the high refractive index contrast between the core and cladding of semiconductor waveguides, nanoscale defects along the waveguide often scatter light into the backward-propagating mode. These reflections could result in unwanted feedback to optical sources or crosstalk in bidirectional interconnects such as those employed in fiber-optic networks. It is often assumed that these reflected waves spatially overlap the forward-propagating waves making it difficult to implement optical circulators or isolators which separate or attenuate light based on its propagation direction. Here, we individually identify and map the near-field mode profiles of forward-propagating and reflected light in a single-mode silicon waveguide using Transmission-based near-field scanning optical microscopy (TraNSOM). We show that unlike fiber-optic waveguides, the high-index-contrast and nanoscale dimensions of semiconductor waveguides create counter propagating waves with distinct spatial near-field profiles. These near-field differences are a previously-unobserved consequence of nanoscale light confinement and could provide a basis for novel elements to filter forward-propagating from reflected light

Kim Stanley Robinson: "Martian Trilogy" "This Is Where We Start Again"

This record consists of the transcript of an interview with Kim Stanley Robinson

A conceptual model for researching the production and potential tourist consumption of popular media texts

This paper attempts to develop a conceptual model of the process of production and consumption of popular media texts (PMTs) to investigate the relationships between the production elements of PMTs and the ways in which particular production values may appeal to potential tourists in diverse settings. The proposed model presumes that there may be structurally causal relationships between highlighted major elements of PMTs production and patterns of consumption associated with audience involvement, subsequent audience loyalty, and intention to visit the locations depicted in the programming in the context of film-induced tourism. The conceptualised model of the process of production and consumption of PMTs is hypothesised by reviewing previous literature and empirical studies. This paper draws attention to trans-national and interdisciplinary perspectives which will enable researchers to develop new ideas and perspectives in exploring the complicated inter-communication processes between PMTs from the production side with audiences/tourists as consumers, and understanding the relationships and mediation between production and consumption of PMTs and associated tourism