Understanding the relationships between the physicochemical properties of engineered nanomaterials and their toxicity is critical for environmental and health risk analysis. However, this task is confounded by material diversity, heterogeneity of published data and limited sampling within individual studies. Here, we present an approach for analysing and extracting pertinent knowledge from published studies focusing on the cellular toxicity of cadmium-containing semiconductor quantum dots. From 307 publications, we obtain 1,741 cell viability-related data samples, each with 24 qualitative and quantitative attributes describing the material properties and experimental conditions. Using random forest regression models to analyse the data, we show that toxicity is closely correlated with quantum dot surface properties (including shell, ligand and surface modifications), diameter, assay type and exposure time. Our approach of integrating quantitative and categorical data provides a roadmap for interrogating the wide-ranging toxicity data in the literature and suggests that meta-analysis can help develop methods for predicting the toxicity of engineered nanomaterials.

SummaryAn integrated simulation tool was developed for assessing the potential release and environmental distribution of nanomaterials (RedNano) based on a life cycle assessment approach and multimedia compartmental modeling coupled with mechanistic intermedia transport processes. The RedNano simulation tool and its web-based software implementation enables rapid “what-if?” scenario analysis, in order to assess the response of an environmental system to various release scenarios of engineered nanomaterials (ENMs). It also allows for the investigation of the impact of geographical and meteorological parameters on ENM distribution in the environment, comparison of the impact of ENM production and potential releases on different regions, and estimation of source release rates based on monitored ENM concentrations. Moreover, the RedNano simulation tool is suitable for research, academic, and regulatory purposes. Specifically, it has been used in environmental multimedia impact assessment courses at both the undergraduate and graduate levels. The RedNano simulation tool can also serve as a decision support tool to rapidly and critically assess the potential environmental implications of ENMs and thus ensure that nanotechnology is developed in a productive and environmentally responsible manner.

A web-based resource for meta-analysis of nanomaterials toxicity is developed whereby the utility of Bayesian networks (BNs) is illustrated for exploring the cellular toxicity of Cd-containing quantum dots (QDs). BN models are developed based on a dataset compiled from 517 publications comprising 3028 cell viability data samples and 837 IC 50 values. BN QD toxicity (BN-QDTox) models are developed using both continuous (i.e., numerical) and categorical attributes. Using these models, the most relevant attributes identified for correlating IC 50 are: QD diameter, exposure time, surface ligand, shell, assay type, surface modification, and surface charge, with the addition of QD concentration for the cell viability analysis. Data exploration via BN models further enables identification of possible association rules for QDs cellular toxicity. The BN models as web-based applications can be used for rapid intelligent query of the available body of evidence for a given nanomaterial and can be readily updated as the body of knowledge expands. Toxicity Models www.advancedsciencenews.com

Silica scaling of RO membranes was evaluated via real-time direct surface imaging demonstrating a capability for detecting the onset of silica scale formation and its evolution. Silica scaling was detected significantly earlier than by traditional flux decline measurements. The observed rate of silica particle nucleation followed classical nucleation theory while the growth of individual silica particles, at the early stages of silica scaling, was governed by diffusional growth. SEM and optical images of the membrane surface suggest that silica scaling occurs through the formation of both primary silica particles and their agglomerates (~1-30 μm), as well as a gel-like silica film embedded with silica particles both of which contribute to permeate flux decline. At low silica saturation index at the membrane surface (SI m ≤ 1.93) silica gel film formation resulted in a smoother and less porous film than at higher silica saturation (SI m ≥ 2.72). At the higher silica saturation levels (SI m =2.72-3.50), silica scaling resulted in larger observed particles as well as rapid permeate flux decline. The silica scale layer thickness was in the range of ~0.1-3.5 µm, with surface roughness being higher by a factor of 2.6-8.3 relative to the native membrane. Results of the present study suggest that there is merit in exploring the application of the present approach for early detection and monitoring of silica scaling in RO plants in support of strategies for silica scale mitigation.

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The potential environmental impact of nanomaterials is a critical concern and the ability to assess these potential impacts is top priority for the progress of sustainable nanotechnology. Risk assessment tools are needed to enable decision makers to rapidly assess the potential risks that may be imposed by engineered nanomaterials (ENMs), particularly when confronted by the reality of limited hazard or exposure data. In this review, we examine a range of available risk assessment frameworks considering the contexts in which different stakeholders may need to assess the potential environmental impacts of ENMs. Assessment frameworks and tools that are suitable for the different decision analysis scenarios are then identified. In addition, we identify the gaps that currently exist between the needs of decision makers, for a range of decision scenarios, and the abilities of present frameworks and tools to meet those needs.

During in-flight emergencies, a pilot's workload increases significantly, and it is often during this period of increased stress that human errors occur that consequently diminish the flight safety. Research studies indicate that many plane crashes can be attributed to ineffective cockpit instrument monitoring by the pilot. This paper entails the development of Flight Guardian ¶ system being first of its kind that aims to provide efficient flight-deck awareness to improve flight safety while assisting the pilot in abnormal situations. The system is intended to be used in older aircraft that cannot easily or cost effectively be modified with modern digital avionic systems. One of the important features of the Flight Guardian system is being not physically connected to the aircraft, which avoids any impact on airworthiness or the need for recertification. For the first time, a composite of techniques including video analysis, knowledge representation, and machine belief representations are combined to build a novel flight-deck warning system. The prototype system is tested in both simulation-based laboratory and real flight environments under the guidance of expert pilots. The overall system performance is evaluated using statistical analysis of experimental results that proved the robustness of the proposed methodology in terms of automated warning generation in hazardous situations.

The technology enhanced learning is believed to be useful in representing the contexts and situations which are harder to explain verbally or bring to the classroom. One of the most important concerns in higher education is to ensure that the learning outcomes are achieved accordingly and learners acquire the desired capability. Most important techniques in supporting learning in higher education sector includes timely and detailed feedback to learners which must include both strengths and weaknesses of learner as well as the future implications of their performance. This paper proposes an online platform called Student Coursework Repository (SCORE) that enables academics to evaluate and provide effective online feedback to students in higher education sector. In this framework, a repository of different feedback mechanisms is made available to academic staff, irrespective of the modules and courses the students are enrolled in. SCORE builds on other literature and research work on feedback management and enables the delivery of other forms of feedback such as audio or video based feedback. SCORE aims to provide a consistent and common tool that can be used in a multidisciplinary environment and is sustainable to support an online and paperless environment.