Introduced Cyprinid (carp) fishes in Western Australia and their management implications

Australia has no native cyprinid species and five introduced species have established self-sustaining populations. This study examines the cyprinid species present in Western Australia and estimates their distribution. The potential for introduced cyprinids to cause environmental impacts is explained and ameliorative action recommended. The presence and distribution of cyprinid species is assessed by examination of museum records, published literature, reported collections, anecdotal evidence and sampling of wetland habitats. Two species, Carassius nuratus (Goldfish) and Cyprinus carpio (Koi carp) are believed to have established populations and a map of estimated distribution is compiled. The capacity for introduced carp to undergo sudden population explosions, long after initial introduction, has been clearly displayed in New Zealand and in the eastern states of Australia. Carp\u27s unique biological and morphological characteristics are examined and the capacity for these characteristics to lead to wider dispersal and environmental impacts in Western Australian wetlands is assessed. The assessment is supplemented by a literature review and a compiled bibliography of published Australian research literature. Principles of effective management of cyprinid populations are discussed and recommendations for amelioration of potential impacts is provided. This is a preliminary study and suggests further avenues of essential research

Investigating the basis of memory-based effects on common ground

Much previous research has investigated the effect of domain-general memory processes on production and comprehension in conversation. In this paper, we present a paradigm in which common ground targets are kept consistent between a participant and two different speakers, and demonstrate a speaker effect that draws participants’ attention away from the common ground target in Experiment 1. Further, we hypothesise that one important factor that promotes speaker identity as a cue for memory processes is that speakers are in conversational partners’ shared attention at the memory coding phase. In Experiments 2 and 3, we demonstrate a non-speaker cue can give rise to a memory-based interference effect when the relevant contextual information is in shared attention but not when it is not. Our results provide an important insight into the interplay of domain-general memory mechanisms and domain specific biases for shared attention

Exploring the existential/universal ambiguity in singular donkey sentences

Although widely discussed in the semantics literature, donkey sentences have been the subject of very little experimental study. In this paper, we present experimental work that is aimed at addressing somewhat open questions around donkey sentences with determiners other than ‘every’ and their susceptibility to both Universal and Existential readings. Our experiments test donkey sentences with ‘every’, ‘no’, ‘some’ and ‘more than two’. By using both verification and act-out tasks, we are able to show that Universal readings are available for donkey sentences with existential determiners (specifically, ‘more than two’), as well as Existential readings. However, our studies fail to show that sentences with ‘no’ have a Universal reading, and they also provide some evidence against the idea that ‘no’ sentences have dual readings

Negative free choice

Free Choice (FC) is an inference arising from the interaction between existential modals and disjunction. Schematically, a sentence of the form permitted(A or B) gives rise to the inference ◊A∧◊B. Many competing theories of FC have been proposed but they can be classified into two main groups: one group derives FC as an entailment, while the other derives it as an implicature. By contrast, Negative Free Choice (NFC), the corresponding inference from negated universal modals embedding conjunction, e.g., not(required(A and B)) to ¬□A∧□B, has been discussed much less, and its existence has even been questioned in the recent literature. This paper reports on three experiments whose results provide clear evidence that NFC exists as an inference, but also indicate that NFC is far less robust than FC. This leaves us with two theoretical possibilities: the uniform approach, which comes in two versions, one deriving both FC and NFC as implicatures, and the other deriving both as entailments, and the hybrid approach that derives FC as an entailment and NFC as an implicature. We argue that the observed difference between FC and NFC is straightforwardly explained under the hybrid approach while it poses a challenge for the uniform approach. We end with a brief discussion of the options we see for the uniform approach and their further consequences

Development of online use of theory of mind during adolescence: An eye-tracking study

We investigated the development of theory of mind use through eye-tracking in children (9-13years old, n=14), adolescents (14-17.9years old, n=28), and adults (19-29years old, n=23). Participants performed a computerized task in which a director instructed them to move objects placed on a set of shelves. Some of the objects were blocked off from the director's point of view; therefore, participants needed to take into consideration the director's ignorance of these objects when following the director's instructions. In a control condition, participants performed the same task in the absence of the director and were told that the instructions would refer only to items in slots without a back panel, controlling for general cognitive demands of the task. Participants also performed two inhibitory control tasks. We replicated previous findings, namely that in the director-present condition, but not in the control condition, children and adolescents made more errors than adults, suggesting that theory of mind use improves between adolescence and adulthood. Inhibitory control partly accounted for errors on the director task, indicating that it is a factor of developmental change in perspective taking. Eye-tracking data revealed early eye gaze differences between trials where the director's perspective was taken into account and those where it was not. Once differences in accuracy rates were considered, all age groups engaged in the same kind of online processing during perspective taking but differed in how often they engaged in perspective taking. When perspective is correctly taken, all age groups' gaze data point to an early influence of perspective information

Modification of bacterial cell membrane to accelerate decolorization of textile wastewater effluent using microbial fuel cells: role of gamma radiation

The aim of the present work was to increase bacterial adhesion on anode via inducing membrane modifications to enhance textile wastewater treatment in Microbial Fuel Cell (MFC). Real textile wastewater was used in mediator-less MFCs for bacterial enrichment. The enriched bacteria were pre-treated by exposure to 1 KGy gamma radiation and were tested in MFC setup. Bacterial cell membrane permeability and cell membrane charges were measured using noninvasive dielectric spectroscopy measurements. The results show that pre-treatment using gamma radiation resulted in biofilm formation and increased cell permeability and exopolysaccharide production; this was reflected in both MFC performance (average voltage 554.67 mV) and decolorization (96.42%) as compared to 392.77 mV and 60.76% decolorization for non-treated cells. At the end of MFC operation, cytotoxicity test was performed for treated wastewater using a dermal cell line, the results obtained show a decrease in toxicity from 24.8 to 0 (v/v%) when cells were exposed to gamma radiation. Fourier-transform infrared (FTIR) spectroscopy showed an increase in exopolysaccharides in bacterial consortium exposed to increasing doses of gamma radiation suggesting that gamma radiation increased exopolysaccharide production, providing transient media for electron transfer and contributing to accelerating MFC performance. Modification of bacterial membrane prior to MFC operation can be considered highly effective as a pre-treatment tool that accelerates MFC performance

Representing Polar Questions

Although the linguistic properties of polar questions have been extensively studied, comparatively little is known about how polar questions are processed in real time. In this paper, we report on three eye-tracking experiments on the processing of positive and negative polar questions in English and French. Our results show that in the early stages, participants pay attention to both positive and negative states of affairs for both positive and negative questions. In the late stages, positive and certain negative polar questions were associated with a bias for the positive state, and this bias appears to be pragmatic in nature. We suggest that different biases in mental representations reflect the hearer’s reasoning about the speaker’s purposes of enquiry

Diversity with Universality

This paper investigates the ‘Diversity’ inferences (D-inferences) arising from disjunction embedded in the scope of a universal quantifier, e.g., Every X is A or B suggests Some Xs are A and Some Xs are B. It has previously been claimed (i) that D-inferences are independent from ‘Negative Universal’ inferences (NU-inferences), which are the negations of Every X is A and Every X is B, but (ii) that for disjunction in the scope of a universal modal the D-inferences cannot be observed independently of the NU-inferences ([3, 7, 9, 13]). Experiment 1 tested the availability of D-inferences in the absence of NU-inferences for the determiner every and the epistemic modal must. Experiment 2 followed up on Experiment 1 by testing the same two quantifiers, only this time the modal must expressed deontic necessity. The results show that, for both types of quantifiers, D-inferences could be derived independently of NU-inferences. While the results for every essentially replicate those reported in [7], the results for must are new and go against the aforementioned claim (ii). In addition, the response time results from both experiments show that D-inferences are associated with response delay effects in the opposite direction to those observed for regular scalar implicatures in similar tasks ([4, 5]). We argue that these findings about the time course of D-inferences raise a new challenge for an implicature-based approach to these inferences