An integrated chemical engineering approach to understanding microplastics

Environmental and health risks posed by microplastics (MPs) have spurred numerous studies to better understand MPs' properties and behavior. Yet, we still lack a comprehensive understanding due to MP's heterogeneity in properties and complexity of plastic property evolution during aging processes. There is an urgent need to thoroughly understand the properties and behavior of MPs as there is increasing evidence of MPs' adverse health and environmental effects. In this perspective, we propose an integrated chemical engineering approach to improve our understanding of MPs. The approach merges artificial intelligence, theoretical methods, and experimental techniques to integrate existing data into models of MPs, investigate unknown features of MPs, and identify future areas of research. The breadth of chemical engineering, which spans biological, computational, and materials sciences, makes it well-suited to comprehensively characterize MPs. Ultimately, this perspective charts a path for cross-disciplinary collaborative research in chemical engineering to address the issue of MP pollution.     

The determination of total germanium in real food samples including Chinese herbal remedies using graphite furnace atomic absorption spectroscopy

This paper outlines the development of a method for the determination of total germanium in foodstuffs utilising graphite furnace atomic absorption. It was found that by varying the drying times interferences could be minimised. Metals including calcium, cobalt, copper, magnesium, nickel, lead and zinc were tested for potential interferences. It was found experimentally that none of the listed metals interfered with this method. The optimal furnace conditions were determined to be; drying for 80 s (85 °C for 30 s, 95 °C for 40 s and 120 °C for 10 s), ashing at 700 °C for 8 s and atomisation at 2600 °C for 3.3 s followed by a tube clean for 2 s at 2800 °C and a lamp current of 5 mA for analysis at 265.2 nm. The method was found to have a linear range of 3.3–125 μg/l with a limit of detection and a characteristic mass of 0.051 and 0.053 ng germanium, respectively. The samples chosen for analysis include vegetables, fruit juices, Chinese herbal remedies and over the counter formulations. It was found that the aloe vera tablet, ginseng tablet and ginger tablet contained 20.83, 5.48 and 9.96 μg/g. Other foods found to contain germanium were potato, garlic and carrot, having 1.85, 2.79 and 0.60 μg/g of germanium. The food found to contain the highest concentration of germanium was Soya mince having 9.39 μg/g.     

A role for lipoxin A₄ as an anti-inflammatory mediator in the human endometrium

Lipoxin A(4) is a lipid mediator that elicits anti-inflammatory and pro-resolution actions via its receptor, formyl peptide receptor 2 (FPR2/ALX). In this study, we aimed to investigate the expression and potential role of lipoxin A(4) and FPR2/ALX in the regulation of inflammation associated with cyclical remodeling of the human endometrium across the menstrual cycle and during early pregnancy. Using quantitative RT-PCR analysis, we found that FPR2/ALX expression is upregulated during the menstrual phase of the cycle and in decidua tissue from the first trimester of pregnancy. We localized the site of expression of FPR2/ALX in menstrual phase endometrium and first-trimester decidua tissue to glandular epithelial cells and cells within the stromal compartment, including cells lining the blood vessels and immune cells. Measurement of serum lipoxin A(4) by ELISA revealed no difference in its levels across the menstrual cycle but an elevation in early pregnancy (P<0.001). We found that lipoxin A(4) was regulated by human chorionic gonadotrophin (hCG) during early pregnancy, because treatment of human decidua tissue with hCG increased lipoxin A(4) release (P<0.01). Finally, we have shown that lipoxin A(4) can suppress phorbol myristate acetate-induced expression of the inflammatory cytokines interleukin 6 and 8 in human endometrium and decidua tissue. These results demonstrate for the first time that lipoxin A(4) and its receptor FPR2/ALX can regulate inflammatory events in the human endometrium and decidua of early pregnancy.     

Millennial-scale records of atmospheric mercury deposition obtained from ombrotrophic and minerotrophic peatlands in the Swiss Jura Mountains

Peat cores from two bogs were used to reconstruct changes in net atmospheric mercury deposition in Switzerland for the past 2-3 millennia. The two records were compared to assess the reliability of peat cores as archives of atmospheric mercury deposition. Net mercury accumulation rates and Hg(ex), an indicator of significant anthropogenic mercury contamination, were calculated for both cores. Both records showed stable background values (0.5-1.9 and 1.0-3.0 microg of Hg m(-2) yr(-1)). In both profiles, mercury accumulation rates began to increase during the 12th century, and Hg(ex) appeared during the 14th century. The late 19th and early 20th centuries have been studied in detail. The profiles match well with the history of local and global mercury emissions. The magnitude of increase from the pre-anthropogenic to anthropogenic period was also very similar in both records. Although the two sites are botanically very similar and lie only 3.5 km apart, accumulation rates at TGE were generally higher than those at EGR. This indicates that, although such records can be used to determine the chronologies of and relative changes in rates of atmospheric mercury deposition, differences in rates of mercury accumulation rates between sites do not necessarily indicate differences in deposition rates of mercury from the atmosphere.     

Culture, cross-role consistency, and adjustment: Testing trait and cultural psychology perspectives.

Trait and cultural psychology perspectives on cross-role consistency and its relation to adjustment were examined in 2 individualistic cultures, the United States (N = 231) and Australia (N = 195), and 4 collectivistic cultures, Mexico (N = 199), the Philippines (N = 195), Malaysia (N = 217), and Japan (N = 180). Cross-role consistency in trait ratings was evident in all cultures, supporting trait perspectives. Cultural comparisons of mean consistency provided support for cultural psychology perspectives as applied to East Asian cultures (i.e., Japan) but not collectivistic cultures more generally. Some but not all of the hypothesized predictors of consistency were supported across cultures. Cross-role consistency predicted aspects of adjustment in all cultures, but prediction was most reliable in the U.S. sample and weakest in the Japanese sample. Alternative constructs proposed by cultural psychologists-personality coherence, social appraisal, and relationship harmony-predicted adjustment in all cultures but were not, as hypothesized, better predictors of adjustment in collectivistic cultures than in individualistic cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Saliva and Plasma Neutralizing Activity Induced by the Administration of a Third bnt162b2 Vaccine Dose

The BNT162b2 vaccine induces neutralizing activity (NA) in serum, but no data are available on whether a third-dose activates specific-immunity within the oral mucosa, representing the primary route of viral-entry. To carefully address this issue, we investigated if such immunity is boosted by SARS-CoV-2-infection; how long it is maintained over-time; and if it protects against the SARS-CoV-2 lineage B.1 (EU) and the emerging Delta and Omicron variants. NA was measured in plasma and saliva samples from: uninfected SARS-CoV-2-Vaccinated (SV), subjects infected prior to vaccination (SIV), and subjects who were infected after the second (SIV2) or the third (SIV3) vaccine dose. Samples were collected immediately before (T0), 15 days (T1), and 90 days (T2) post third-dose administration (SV and SIV), or 15 days post-infection (SIV2 and SIV3). In all the enrolled groups, NA in plasma and saliva: (i) was higher against EU compared to the other variants at all time-points (SV: T0 and T1, EU vs. both Delta and Omicron p < 0.001; T2 p < 0.01) (SIV: T0, EU vs. Delta p < 0.05; EU vs. Omi p < 0.01; T1 and T2 EU vs. Delta p < 0.01; EU vs. Omi p < 0.001); (ii) was boosted by the administration of the third dose; iii) declined over-time, albeit being detectable in almost all subjects at T2. The monitoring of NA over time will be important in clarifying if different NA levels may influence either acquisition or course of infection to properly plan the timing of a fourth vaccine dose administration.     

In situ slip estimation for mobile robots in outdoor environments

Accounting for wheel–terrain interaction is crucial for navigation and traction control of mobile robots in outdoor environments and rough terrains. Wheel slip is one of the surface hazards that needs to be detected to mitigate against the risk of losing the robot's controllability or mission failure occurring. The open problems in the Terramechanics field addressed are (1) the need for in situ wheel-slippage estimation in harsh environments using low-cost/power and easy to integrate sensors, and (2) removing the need for prior information of the soil, which is not always available. This paper presents a novel slip estimation method that utilizes only two proprioceptive sensors (IMU and wheel encoder) to estimate the wheel slip using deep learning methods. It is experimentally shown to be real-world feasible in outdoor, uneven terrains without prior soil information assumptions. Comparison with previously used machine learning algorithms for continuous and discrete slip estimation problems show more than 9% and 14% improvement in estimation performance, respectively.     

Lead-Free,Luminescent Perovskite Nanocrystals Obtained through Ambient Condition Synthesis

Heterovalently substituting toxic lead is an increasingly popular design strategy to obtain environmentally sustainable variants of the exciting material class of halide perovskites. Perovskite nanocrystals (NCs) obtained through solution-based methods exhibit exceedingly high optical quality. Unfortunately, most of these synthesis routes still require reaction under inert gas and at very high temperatures. Herein a novel synthesis routine for lead-free double perovskite (LFDP) NCs is presented. An approach based upon the hot injection and ligand-assisted reprecipitation (LARP) methods to achieve a low-temperature and ambient atmosphere-based synthesis for manganese-doped Cs₂NaBiCl₆ NCs is presented. Mn incorporation is critical for the otherwise non-emissive material, with a 9:1 Bi:Mn precursor ratio maximizing the bright orange photoluminescence (PL) and quantum yield (QY). Higher synthesis temperatures slightly increase the material's performance, yet NCs synthesized at room temperature are still emissive, highlighting the versatility of the synthetic approach. While the material's indirect bandgap limits its appeal for optoelectronics, this feature could benefit photocatalysis due to longer carrier lifetimes. Moreover, the developed synthesis is facile and can rapidly be adapted to other more viable material compositions and up-scaled to realize applications directly.     

Liquid Crystals as Multifunctional Interfaces for Trapping and Characterizing Colloidal Microplastics

Identifying and removing microplastics (MPs) from the environment is a global challenge. This study explores how the colloidal fraction of MPs assemble into distinct 2D patterns at aqueous interfaces of liquid crystal (LC) films with the goal of developing surface-sensitive methods for identifying MPs. Polyethylene (PE) and polystyrene (PS) microparticles are measured to exhibit distinct aggregation patterns, with addition of anionic surfactant amplifying differences in PS/PE aggregation patterns: PS changes from a linear chain-like morphology to a singly dispersed state with increasing surfactant concentration whereas PE forms dense clusters at all surfactant concentrations. Statistical analysis of assembly patterns using deep learning image recognition models yields accurate classification, with feature importance analysis confirming that dense, multibranched assemblies are unique features of PE relative to PS. Microscopic characterization of LC ordering at the microparticle surfaces leads to predict LC-mediated interactions (due to elastic strain) with a dipolar symmetry, a prediction consistent with the interfacial organization of PS but not PE. Further analysis leads to conclude that PE microparticles, due to their polycrystalline nature, possess rough surfaces that lead to weak LC elastic interactions and enhanced capillary forces. Overall, the results highlight the potential utility of LC interfaces for rapid identification of colloidal MPs based on their surface properties.