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Highly efficient water desalination by capacitive deionization on biomass-derived porous carbon nanoflakes
No full textCapacitive deionization (CDI) works by using the electrical double layer on various materials including nanoporous carbons to separate ions from saline water. To help realize industrial application, there has been an increasing interest in the exploration of carbon materials from low cost, eco-friendly and abundant biomass for CDI to align with the demands of sustainable development strategies. Herein we report pyrolysis of xylose with KHCO to prepare hierarchically porous carbon nanoflakes which display a satisfactory salt adsorption capacity of 16.29 mg g. This novel strategy can design highly efficient carbon materials from naturally-developed biomass materials with its low preparation cost, environmentally friendliness and superior desalination performance. Our xylose-derived hierarchically porous carbon nanoflakes are promising for potential industrial application for CDI
The presence of selected UV filters in a freshwater recreational reservoir and fate in controlled experiments
No full textUV filters present in sunscreen and other cosmetics are directly released into the environment during aquatic recreational activities. The extent to which the wide range of UV filters pose a risk to the environment remains unclear. This study investigated the occurrence and dissipation of selected organic UV filters at a recreational site (Enoggera Reservoir, Queensland, Australia) over 12 h. Furthermore, different possible degradation processes were investigated in a controlled off-site experiment with surface water exposed to natural light. Half-lives were estimated for ten UV filters. In Enoggera Reservoir, seven UV filters were detected, of which the most prevalent were octocrylene, avobenzone (BMDBM) and enzacamene (4-MBC). Summed concentrations of the seven UV filters ranged from 7330 ng L at 13:00 h to 2550 ng L at 21:00 h. In the degradation experiment, four UV filters showed no significant change over time. The fate of these compounds in the environment is likely to be mainly influenced by dispersion. Half-lives of the remaining UV filters were 6.6 h for amiloxate (IMC), 20 h for benzophenone 1, 23 h for octinoxate (EHMC), 30 h for 3-benzylidene camphor, 34 h for 4-MBC and 140 h for dioxybenzone (BP8). The degree of susceptibility to photodegradation and biodegradation was generally consistent within a structural class. The fate and half-lives of UV filters are variable and should be considered on a per site basis when assessing environmental risk
Predicting waiting time to treatment for emergency department patients
No full textBackground: The current systems of reporting waiting time to patients in public emergency departments (EDs) has largely relied on rolling average or median estimators which have limited accuracy. This study proposes to use machine learning (ML) algorithms that significantly improve waiting time forecasts. Methods: By implementing ML algorithms and using a large set of queueing and service flow variables, we provide evidence of the improvement in waiting time predictions for low acuity ED patients assigned to the waiting room. In addition to the mean squared prediction error (MSPE) and mean absolute prediction error (MAPE), we advocate to use the percentage of underpredicted observations. The use of ML algorithms is motivated by their advantages in exploring data connections in flexible ways, identifying relevant predictors, and preventing overfitting of the data. We also use quantile regression to generate time forecasts which may better address the patient's asymmetric perception of underpredicted and overpredicted ED waiting times. Results: Using queueing and service flow variables together with information on diurnal fluctuations, ML models outperform the best rolling average by over 20 % with respect to MSPE and quantile regression reduces the number of patients with large underpredicted waiting times by 42 %. Conclusion: We find robust evidence that the proposed estimators generate more accurate ED waiting time predictions than the rolling average. We also show that to increase the predictive accuracy further, a hospital ED may decide to provide predictions to patients registered only during the daytime when the ED operates at full capacity, thus translating to more predictive service rates and the demand for treatments
Knowledge Identity (KI): A New Approach to Integrating Knowledge Management into Enterprise Systems
No full textAmines modulation and passivation yields record perovskite optoelectronic devices
No full textPrimary amines function well in defect passivation, crystal modulation, and surface functionalization in perovskite solar cells and perovskite light-emitting diodes, yielding record performances
The application of statistical shape modeling for lung morphology in aerosol inhalation dosimetry
No full textEven with the advance in medical imaging techniques such as CT/MRI, it is still challenging and time-consuming to reconstruct anatomically accurate lung geometries. It is even more challenging to study variability in inhalation dosimetry or pulmonary drug delivery, which requires a large cohort of lung models to ensure statistically significant results. This study used the statistical shape modeling (SSM) that bases on a limited number of lung models (40) to generate infinitely large numbers of parameterized models, which can span all major features inherent in the database of lung geometries. We demonstrated this model in lung models with more than 400 outlets (G9), which first identified the principal components (PCs) of base models, and then regenerated new models by systematically varying the mode (eigenvector) and its eigenvalues. The new models included airway remodeling at varying locations (left upper lobe and right lower lobe) and with varying levels of airway distensibility (compliance) and constriction (resistance). Airflow and aerosol dynamics within these lung geometries were numerically computed and compared. Results showed that even though the airway remodeling can be local, its influences on flow partition and deposition distribution can be global. Asthma-induced bronchiolar constriction, when severe, can strikingly alter the airflow and particle deposition mapping throughout the lungs. The highest deposition variability due to airway remodeling was found to come from particles of 4–10 μm in the upper lobes, and of 10–20 μm in the lower lobe. Statistical shape modeling is an imaging processing method that has often been used in computer sciences. This is the first study, to the author's knowledge, that SSM was applied in lung models with high complexity to quantify the resultant variances from these geometry remodeling. This method was also applied to lung models with 3000 outlets (G11) to generate diseased lung models at varying locations
Studying the metabolism of epithelial-mesenchymal plasticity using the seahorse XFe96 extracellular flux analyzer
No full textThe critical role of metabolism in facilitating cancer cell growth and survival has been demonstrated by a combination of methods including, but not limited to, genomic sequencing, transcriptomic and proteomic analyses, measurements of radio-labelled substrate flux and the high throughput measurement of oxidative metabolism in unlabelled live cells using the Seahorse Extracellular Flux (XF) technology. These studies have revealed that tumour cells exhibit a dynamic metabolic plasticity, using numerous pathways including both glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) to support cell proliferation, energy production and the synthesis of biomass. These advanced technologies have also demonstrated metabolic differences between cancer cell types, between molecular subtypes within cancers and between cell states. This has been exemplified by examining the transitions of cancer cells between epithelial and mesenchymal phenotypes, referred to as epithelial-mesenchymal plasticity (EMP). A growing number of studies are demonstrating significant metabolic alterations associated with these transitions, such as increased use of glycolysis by triple negative breast cancers (TNBC) or glutamine addiction in lung cancer. Models of EMP, including invasive cell lines and xenografts, isolated circulating tumour cells and metastatic tissue have been used to examine EMP metabolism. Understanding the metabolism supporting molecular and cellular plasticity and increased metastatic capacity may reveal metabolic vulnerabilities that can be therapeutically exploited. This chapter describes protocols for using the Seahorse Extracellular Flux Analyzer (XFe96), which simultaneously performs real-time monitoring of oxidative phosphorylation and glycolysis in living cells. As an example, we compare the metabolic profiles generated from two breast cancer sublines that reflect epithelial and mesenchymal phenotypes, respectively. We use this example to show how the methodology described can generate bioenergetic results that in turn can be correlated to EMP phenotypes. Normalisation of bioenergetic studies should be considered with respect to cell number, and to potential differences in mitochondrial mass, itself being an important bioenergetics endpoint
There is no such thing as a mindful binge: How mindfulness disrupts the pathway between anxiety and impulsivity on maladaptive eating behaviours
No full textResearch using the Revised Reinforcement Sensitivity Theory (RST) to investigate the individual differences in overconsumption of food has consistently found those who over-consume to be higher in conflict sensitivity (i.e., Behavioural Inhibition System (BIS)) and impulsivity than those who do not overconsume. However, the exact mechanisms through which these individual differences operate, and the identification of potential protective factors that may disrupt such pathways are not clear. The current study tested the moderating role of impulsivity and trait mindfulness in the pathway between BIS and two types of overconsumption; binge eating and grazing. Undergraduate students (n = 245, M = 22.48 years of age, SD = 8.95, 77% female) completed self-report measures of RST, trait mindfulness, binge eating symptoms, and grazing symptoms. Results showed that impulsivity moderated the pathway between BIS and both binge eating and grazing. With mindfulness included in the model, a two-way interaction was found for binge eating, and a three-way interaction was found for grazing. Results suggest the effect of trait mindfulness on the BIS/impulsivity pathway is unique for differing severities of overconsumption, and that RST systems, trait mindfulness and target behaviours may be worthy of consideration when selecting intervention modalities
A sensitive, high-throughput fluorescent method for the determination of lactoperoxidase activities in milk and comparison in human, bovine, goat and camel milk
No full textLactoperoxidase (LPO) is one of the major antibacterial ingredients in milk and an extensively employed indicator for milk heat treatment. The traditional method for LPO activity measurement using ABTS (2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonate) cannot achieve high sensitivity and is affected by indigenous milk thiocyanate. A more sensitive microplate fluorescent assay was developed by monitoring generation of red-fluorescent resorufin from LPO catalysed oxidation of Amplex® Red (1-(3,7-dihydroxyphenoxazin-10-yl)ethanone) in this study. The assay is particularly suitable for milk LPO activity measurement as it eliminates the influences of indigenous milk hydrogen peroxide and thiocyanate. The method limit of detection was 7.1x10−6\ua0U/mL of LPO in milk and good intra-run and inter-run precision was obtained. The LPO activities ranked as bovine\ua0>\ua0goat\ua0>\ua0camel\ua0>\ua0human in the four types of milk analysed. The high sensitivity and low cost of this assay makes it suitable for LPO activity analyses in both laboratory and commercial scales
Isolation and evaluation of anti-listeria lactococcus lactis from vegetal sources
No full textThis chapter describes methods used to isolate, identify, and partially characterize lactic acid bacteria (LAB) which exhibit inhibitory activity against Listeria monocytogenes from foods. Vegetal (plant based) sources\ua0are rich in naturally occurring LAB and therefore provide an easily accessible source of strains with potential antimicrobial activity for use in food-processing applications. From our previous work, the majority of LAB with inhibitory activity against L. monocytogenes were identified as generally recognized as safe (GRAS) Lactococcus lactis. Although these bacteria are most commonly known for their role in industrial dairy fermentations, they are believed to have originally derived from natural plant-based habitats. These isolates with anti-Listeria activity were all found to carry the genes involved in the production of nisin, which is an approved food-grade preservative (E234). These isolates may find various applications for in situ production of nisin allowing control of L. monocytogenes in various fermented and non-fermented foods and other environments
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