Longitudinal trends in river functioning: Patterns of nutrient and carbon processing in three Australian rivers

Understanding longitudinal trends in the processing of carbon in rivers represents a much conceptualised, but infrequently tested, issue in aquatic ecology. In this study, we conducted concurrent longitudinal examinations of three very different rivers in eastern Australia to determine whether general principles in river functioning exist across broad geographic and hydrologic scales. Specifically, we examined trends in ambient basic water chemistry, nutrient concentrations, dissolved organic carbon (DOC), extracellular enzymes and food web structure and functioning and conducted bioassays to examine the degree to which DOC and nutrients limit heterotrophic bacterial respiration. These parameters revealed striking similarities across all sites. For metazoan communities, stable isotope analysis showed that algal carbon was the dominant basal resource utilised by consumers in all three rivers, suggesting that in‐stream primary producers strongly underpin trophic pathways regardless of the position within a catchment or catchment condition. Analyses of extracellular enzymes revealed that microbial communities are actively utilising DOC at all sites. In fact, heterotrophic microbial respiration was strongly limited by DOC at all sites, with nutrient additions resulting in only relatively minor increases in respiration. Ultimately, this study demonstrates that DOC and algal carbon are critically important drivers of ecosystem processes in Australian riverine ecosystems. Furthermore, across all of our sites and rivers, ambient nutrient concentrations did not influence carbon processing. The consistent longitudinal trends in river function identified in this study provide useful insights for catchment managers and modellers with respect to identifiying key principles that underpin ecosystem functioning in Australian rivers. Copyright © 2009 John Wiley & Sons, Ltd.     

Challenges and Rewards in Using Parametric or Concatenative Speech Synthesis

Highest quality synthetic voices remain scarce in both parametric synthesis systems and in concatenative ones. Much synthetic speech lacks naturalness, pleasantness and flexibility. While great strides have been made over the past few years in the quality of synthetic speech, there is still much work that needs to be done. Now the major challenges facing developers are how to provide optimal size, performance, extensibility, and flexibility, together with developing improved signal processing techniques. This paper focuses on issues of performance and flexibility against a background containing a brief evolution of speech synthesis; some acoustic, phonetic and linguistic issues; and the merits and demerits of two commonly used synthesis techniques: parametric and concatenative. Shortcomings of both techniques are reviewed. Methodological developments in the variable size, selection and specification of the speech units used in concatenative systems are explored and shown to provide a more positive outlook for more natural, bearable synthetic speech. Differentiating considerations in making and improving concatenative systems are explored and evaluated. Acoustic and sociophonetic criteria are reviewed for the improvement of variable synthetic voices, and a ranking of their relative importance is suggested. Future rewards are weighed against current technical and developmental challenges. The conclusion indicates some of the current and future applications of TTS.     

A new tangible user interface for machine learning document review

This paper describes a tool for assisting lawyers and paralegal teams during document review in eDiscovery. The tool combines a machine learning technology (CategoriX) and advanced multi-touch interface capable of not only addressing the usual cost, time and accuracy issues in document review, but also of facilitating the work of the review teams by capitalizing on the intelligence of the reviewers and enabling collaborative work.     

Evaluation of the mechanical properties and diffusion coefficients of osmodehydrated melon cubes

The objective of this work was to evaluate the influence of osmotic agents, their concentration and temperature, on the mass transfer kinetics and mechanical properties of osmodehydrated melon cubes. Samples were immersed in a hypertonic solution of sucrose or maltose up to 8 h under controlled temperature and agitation. Water loss, sugar gain and mechanical properties were analysed throughout the process. Mass transfer kinetics was modelled according to Peleg and Fick equations. Higher water loss, lower sugar uptake and stress at rupture values more similar to fresh fruit were observed in samples treated with maltose solutions. Peleg’s model showed the best adjustment to all the experimental data, however the k₁ and k₂ parameters did not show a clear trend with the solution concentration or temperature increase. The effective diffusivity obtained using Fick’s equation varied from 3.93 × 10^?9 to 6.45 × 10^?9m² s^?1 for water loss and from 7.57 × 10^?10 to 3.14 × 10^?9m² s^?1 for sugar gain.     

Divorce and the Housing Movements of Owner-Occupiers: A European Comparison

Divorce usually carries a range of economic consequences for both men and women, the housing situation of the ex-partners being among the most important ones. So far, however, the housing consequences of this life event, and in particular the way these are influenced by institutional arrangements, have been somewhat of a neglected topic. This paper focuses on one aspect of this process, more specifically the impact of divorce on tenure changes of homeowners, using comparative panel data for 12 European countries. It is concluded that although divorce significantly raises the odds of experiencing a tenure change for homeowners in all countries under consideration, this process is fairly similar across European welfare states. While institutional arrangements mitigating the economic consequences of divorce for women do not seem to explain much variation between countries, cross-national differences in tenure changes for homeowners are partly influenced by social housing policies and the extent of family support.     

Suspension concentration profiles during rapid gravity filter backwashing

Rapid gravity, granular media filters are widely used in the water and wastewater treatment industries. Regular backwashing to clean the filters is a vital part of their efficient operation. Experimental data on the development of suspension concentration profiles through laboratory scale filter beds during the backwash process were obtained. Previous attempts to obtain and record backwash profiles of this type have been unsuccessful due to the limited range of existing turbidimeters. The results have been used to validate a new model developed by the authors.     

Preschoolers' moral actions and emotions in Prisoner's Dilemma.

The moral acts of 19 dyads of 4-yr-olds in a cognitively simplified version of Prisoner's Dilemma game were analyzed in relationship to their friendship, emotions, and processes of conflict resolution. Degree of friendship was rated by teachers; 2 sociologists used a Q-sort of group processes to describe the dyads' interactions. The emotions of each S were coded from videotape independently of his/her partner's and with the sound turned off. Moral acts were categorically identified as equalization, reparation, stalemate, default, and betrayal. These acts were also assigned scale scores on a dimension of moral sensitivity that was independently derived from separate work with 143 undergraduates, who judged the 5 acts in all possible paired comparisons and then rated the moral difference between each pair. These data almost perfectly fitted a model of increasing monotonic function. The degree of friendship between the dyads and their interactive processes—group orientation, positive emotional tone, and active involvement—were positively related to sensitive moral action. Their emotions were related to concurrent acts, and more importantly, predicted their subsequent acts even though they seldom talked about morality. Results suggest that if social scientists' search for practical morality is to be successful, emotional communication needs to be considered. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)