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Rapid, in-line characterisation of a vortex mixer and its use for green synthesis of nanosilica
Full text linkScaling-up nanomaterials synthesis is complex due to a lack of understanding of the effects of mixing and production scales on the process chemistry. Use of intensified mixer provides a way forward to address these challenges. To that end, this study represents a first step towards exploring the use of a vortex mixer to study the effects of mixing on the formation of nanosilica using a bioinspired green synthesis. Firstly, we designed a multi-inlet vortex mixer (MIVM) and characterised its mixing profile. To facilitate this process, enable faster measurements and address variability in the results, we designed and implemented an in-line measurement setup. The in-line setup was then used to characterise a vortex mixer and the results show excellent match between the custom-built setup and the traditional offline method, thus demonstrating its ability to provide a rapid and simple way for quantifying mixing. Finally, we explored the implementation of a MIVM for the green synthesis of silica for the first time. We observed that at higher flowrates when MIVM provides fast mixing, the conversion of the precursor, the yield and the product properties approached those of silica obtained from an ideally mixed batch system. Collectively, these results provide a clear pathway to help design future investigations to correlate the mixing conditions with emerging nanomaterials syntheses as well as enable their scale-up by implementing adequate mixing processes
Flash Profile method, is it suitable for complex multi-layered products? Application to strawberry-filled biscuits: a “SWEET project”
Full text linkComposite foods are consumed daily, but understanding their sensory properties is a major challenge. This study aims to evaluate the efficiency of Flash Profile (FP) method to characterize strawberry-filled biscuits properties, in a context of sugar reduction. Investigations were carried out on fillings (with/without added sugar, with/without strawberry aroma), then biscuits (with sugar or maltitol or sorbitol, with/without vanilla aroma) and finally on the complex fruit-filled biscuits, corresponding to a progressive matrix complexification strategy.
FP allowed a discrimination of the products for the 3 matrices according to their formulation and flavouring. Fruit fillings and biscuits were described with both flavour and texture attributes, whereas fruit-filled biscuits were mainly described with texture attributes. This texture predominance could result from complex changes of texture perceived during chewing. Panellists may also have focused on the first perceived characteristics or on the product's most distinguishing features to ease the task.
FP was efficient to discriminate samples in each set of samples according to formulation. The characteristics allowing differentiation between samples varied depending on the matrix. Flavour attributes were mainly used for fluid matrices while texture was dominant for solid matrices. In our study, all panellists evaluated the 3 sets of products in the same order which could have influence their evaluation of complex products during the last session. Further investigations about the evaluation of complex solid products with FP may determine if texture is always dominant, even with a lower number of products
Sewer misconnection: Recommendations for increasing sewer connections in low-income urban communities in Dhaka, Bangladesh
Full text linkIn Dhaka, Bangladesh, sewer misconnections persist despite sewer infrastructure expansion by the Dhaka Water Supply and Sewerage Authority (DWASA). This mixed-method cross-sectional study aimed to develop targeted, evidence-based interventions to increase sewer connections in urban communities. We surveyed 384 households and conducted 10 in-depth interviews and two focus group discussions across five DWASA zones. Using the Risks, Attitudes, Norms, Abilities, and Self-regulation (RANAS) framework, we identified key psychological factors influencing sewer connection behaviours. Building on these insights, we mapped psychological factors to Behaviour Change Techniques (BCTs) to develop tailored interventions. Households those were not-connected to sewer exhibited significantly lower awareness of sanitation-related health risks, less confidence in navigating connection procedures, and weaker perceptions of the social benefits of sewer linkage. Qualitative findings revealed widespread dissatisfaction with dysfunctional drainage systems, high connection costs, inadequate maintenance support from DWASA, and bureaucratic delays as significant barriers. These results highlight a complex interplay of psychological, financial, and administrative challenges limiting sewer uptake. Based on these insights, we propose a comprehensive intervention package integrating health education to improve risk awareness, community role models to shift social norms, practical technical guidance to simplify connection processes, and income-adjusted financial incentives to ease economic burdens. The study emphasises the urgent need for integrated, multi-sectoral strategies that address behavioural, structural, and economic barriers simultaneously. Implementing these interventions reduces sewer misconnections, an often-overlooked source of environmental contamination and public health risk, and would advance equitable and sustainable sanitation in rapidly urbanising cities like Dhaka
Insights into the role of Ce and Sm in improving low-temperature NH3-SCR performance over Ce-Sm/Cu-SSZ-13 coupled catalysts
No full textThe increasingly stringent requirements for controlling nitrogen oxide (NOx) emissions during the cold start conditions of diesel engines serve as a powerful driving force to enhance the low-temperature NH3-SCR performance of state-of-the-art commercial Cu-SSZ-13. In this study, the coupled catalysts were synthesized to create additional active sites for NO oxidation and NH3 adsorption/activation, and the synergistic effect between Cu species and CeO2/Sm2O3 leads to a substantial boost in the low-temperature NH3-SCR activity of CSZ. The results suggest that 6 % Ce-2 % Sm/CSZ, as the optimal coupled catalyst, achieves a NOx conversion of 93.1 % at 200 °C, significantly higher than that of CSZ. The coupled CeO2 and Sm2O3 enhance the number of both Brønsted and Lewis acid sites on CSZ, promoting the adsorption and activation of NH3. Therefore, 6 % Ce-2 % Sm/CSZ can form more NH+4 adsorbed on the Lewis acid sites, which reacts with free ionic nitrates to form NH4NO3. More importantly, the coupled Sm2O3 facilitates the conversion of NH4NO3 by NO to easily decomposable NH4NO2. In addition, additional oxygen vacancies provided by Ce3+ can adsorb O2 and promote the transport of oxygen ions, and electron donation from Sm3+ to [ZCu2+(OH)]+ enhances the low-temperature activity of the latter. Ultimately, the low-temperature NH3-SCR performance of CSZ is improved via a synergistic effect. The NH3-SCR reaction over 6 % Ce-2 % Sm/CSZ co-follows the Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms
Antibacterial activity of cerium oxide nanoparticles: a systematic review and meta-analysis study
No full textIntroduction
This meta-analysis examined the antibacterial efficacy of Cerium Oxide Nanoparticles (CeO2 NPs) through statistical analysis of published data.
Method
Following a comprehensive literature search and systematic screening, data were extracted and analyzed using STATA software to calculate pooled standard mean differences and effect sizes.
Results
Analysis of data from 58 articles (218 experiments) demonstrated significant antibacterial activity. Analysis of 189 agar diffusion tests showed substantial effect (EF = 15.04; 95% CI = 14.793–15.277; p < 0.0001). Subgroup analysis revealed greater efficacy for particles larger than 50 nm and rod-shaped nanoparticles. CeO2 NPs were effective against both Gram-positive (EF = 18.194) and Gram-negative (EF = 14.049) bacteria, including Escherichia coli and Staphylococcus aureus. Compared to conventional antibiotics, CeO2 NPs were generally less effective (SMD = -2.846, p < 0.0001) but performed comparably to Amoxicillin, Streptomycin, Linezolid, and Clindamycin. MIC and CFU tests confirmed significant growth-inhibitory effects across multiple bacterial species.
Conclusion
CeO2 NPs demonstrate significant broad-spectrum antibacterial activity, suggesting potential against antibiotic-resistant bacteria. Future research should explore synergistic effects with standard antibiotics
Theory of change: Impact evaluation for information literacy research and practice
No full textThis chapter presents an argument for the adoption of the Theory of Change approach to impact evaluation to support information literacy modes of inquiry. There is increasing interest in evaluation of information literacy teaching development and research, and Theory of Change has been shown to provide a useful framework for evaluation. The chapter covers the principles of the design of Theory of Change from its beginnings as an approach to impact evaluation in community development projects, and how it can be used as a participatory and inclusive method to engage stakeholders in articulating the intended outcomes for a project, and how these should be achieved. Examples are provided of the use of Theory of Change to evaluate curriculum development projects and information literacy initiatives in a Higher Education context. The chapter concludes by asserting the value of Theory of Change for providing a standardized and shareable framework for articulating the value of information literacy initiatives
A platform for CRISPRi-seq in Streptomyces albidoflavus
No full textStreptomyces produce a multitude of secondary metabolites, which have been exploited in drug discovery campaigns for more than three-quarters of a century. Our understanding of microbial physiology has been revolutionized by genome sequencing and large-scale functional studies. Technology for genome-wide investigations in Streptomyces species, however, has lagged behind that for other bacterial systems, hindering exploitation of unprecedented quantities of genomic data. Here, we develop a platform for en masse clustered regularly interspaced short palindromic repeats interference sequencing (CRISPRi-seq) for Streptomyces spp. By performing CRISPRi-seq with 2,160 unique sgRNAs targeting all operons (432 operons) encoding membrane transporters (629 genes) representing 1.1Mb of the 6.8Mb genome for S. albidoflavus, combined with hit validation, we discovered that only a small proportion (13 of 432 operons, 25 kb) contribute positively to fitness. Our work provides both a first-in-class platform for high-throughput functional genomics and a generalized blueprint for en masse screens in Streptomyces species
Water Incorporation Mechanisms and Effects in MgSiO3-Majorite Under High Temperature and Pressure Conditions
Full text linkThe incorporation of water in high-pressure minerals is essential for the water cycle within the interiors of terrestrial planets. Majoritic garnet, a major component in the mantles of Earth and Mars, plays a significant role in this context. In this study, we use first-principles simulations to explore water incorporation mechanisms in MgSiO3-majorite, which is a key end-member of majoritic garnet, at conditions up to 2,000 K and 20 GPa. By dealing with the relationship between chemical potential and the Gibbs free energy changes for the reactions at equilibrium conditions, we determine the ratios of the seven potential hydrous defects. Our results reveal that the Si2 and Si3 defects, which are of the hydrogarnet-type, dominate water incorporation in MgSiO3-majorite. In addition, we evaluate the effects of these hydrous defects on seismic wave velocities. The presence of Si2 and Si3 defects, with an expected water concentration of ∼700 ppm, has a small effect on both P-wave and S-wave velocities. Nevertheless, the influence of water on lateral variations in the seismic wave velocities of MgSiO3-majorite, which is opposite to that found for ringwoodite, offers a potential tool for investigating compositional heterogeneities in hydrated regions of planetary mantles
A bioactive hydrogel harnessing the regenerative potential of notochordal cells serves as instructive cell carrier for nucleus pulposus repair
Full text linkNatural biomatrices are popular owing to their ability to mimic tissue-specific biological properties. These properties are crucial for the intervertebral disc, a particularly demanding tissue whose degeneration is a major cause of chronic lower back pain. Degeneration starting within the core of the disc, the nucleus pulposus (NP), is marked by the loss of notochordal cells (NCs) and associated-healthy extracellular matrix. The regulative potential of the NC-secretome was exploited through a PEG-based hydrogel formulated with decellularized porcine notochordal cell matrix (dNCM). Even under conditions which mimic the degenerate niche, the hydrogel supported maintenance of the native porcine NC phenotype, well-known for the difficulty in preserving their vacuolated phenotype. dNCM-PEG hydrogel carrying human mesendodermal progenitors (hMEPCs; iPS-derived and capable of differentiating into NCs), was injected into NP explants with enzymatically induced matrix degradation and subjected to dynamical loading. hMEPCs engrafted successfully and a healthy disc cell phenotype was observed. Injection of dNCM+hMEPCs into degenerated discs in a pilot experimental dog study indicated that ∼7% of the 0.5 million hMEPCs engrafted. Single cell RNAseq analysis showed over 30% of the engrafted and recovered hMEPCs co-expressed Collagen Type II and Aggrecan consistent with a functional phenotype. No tumorigenic or systemic immunogenic side effects were observed. At the tissue level, TBXT expression, as well as matrix quality, were enhanced in the treated degenerate disc tissues. Together, this study highlights the translational potential of combining cell-based therapies with a bioactive material containing part of the NC secretome, warranting further development and validation
Robots with hearts: How in-store AI’s task types impact brand attitude and ethicality
No full textRecent advancements in robotics and conversational Artificial Intelligence (AI) have expanded their capability to handle complex customer interactions. As businesses integrate robots for consumer encounters, they must decide how to allocate tasks between in-store AI and human employees. While previous research has examined consumer responses to AI, limited attention has been given to how different task distributions influence consumer attitudes. Through four experimental studies, we demonstrate that assigning empathetic (vs. mechanical) tasks to in-store AI while relegating mechanical (vs. empathetic) tasks to human service employees leads to diminished brand attitudes and negative perceptions of brand ethicality. Furthermore, the impact of AI task type on brand attitude is amplified for small brands, indicating a moderating role of brand size. Our findings highlight an intricate ethical dilemma: despite AI’s growing capabilities to automate socioemotional tasks, this can be perceived as ethically problematic compared to automating chores that frees human labor
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