The Role of Ultrasound in the Preparation of Zein Nanoparticles/Flaxseed Gum Complexes for the Stabilization of Pickering Emulsion

Ultrasound is one of the most commonly used methods to prepare Pickering emulsions. In the study, zein nanoparticles-flaxseed gum (ZNP-FSG) complexes were fabricated through various preparation routes. Firstly, the ZNP-FSG complexes were prepared either through direct homogenization/ultrasonication of the zein and flaxseed gum mixture or through pretreatment of zein and/or flaxseed gum solutions by ultrasonication before homogenization. The Pickering emulsions were then produced with the various ZNP-FSG complexes prepared. ZNP-FSG complexes and the final emulsions were then characterized. We found that the complex prepared by ultrasonication of zein as pretreatment followed by homogenization of the ZNP with FSG ((ZNPU-FSG)H) exhibited the smallest turbidity, highest absolute potential value, relatively small particle size, and formed the most stable complex particles. Meanwhile, complex prepared through direct ultrasonication plus homogenization on the mixture ((ZNP-FSG)HU) showed significantly decreased emulsifying properties and stability. Compared with the complex without ultrasonic treatment, the complex and emulsion, which prepared by ultrasonicated FSG were extremely unstable, and the phase separation phenomenon of the emulsion was observed 30 min after preparation. The above conclusions are also in line with the findings obtained from the properties of the corresponding emulsions, such as the droplets size, microstructure, freeze-thaw stability, and storage stability. It is, therefore, clear that to produce stable Pickering emulsion, ultrasonication should be avoided to apply together at the end of ZNP-FGS complex preparation. It is worth noticing that the emulsions prepared by complex with ultrasonicated zein (ZNPU-FSG)H are smaller, distributed more uniformly, and are able to encapsulate oil droplets well. It was found that the emulsions prepared with ZNPU-FSG remained stable without serum phase for 14 days and exhibited improved stability at low-temperature storage. The current study will provide guidance for the preparation of protein–polysaccharide complexes and Pickering emulsions for future work.

Smoke-charged vortices in the stratosphere generated by wildfires and their behaviour in both hemispheres: comparing Australia 2020 to Canada 2017

The two most intense wildfires of the last decade that took place in Canada in 2017 and Australia in 2019–2020 were followed by large injections of smoke in the stratosphere due to pyroconvection. It was discovered by Khaykin et al. (2020) and Kablick et al. (2020) that, after the Australian event, part of this smoke self-organized as anticyclonic confined vortices that rose in the mid-latitude stratosphere up to 35 km. Based on CALIOP observations and the ERA5 reanalysis, this new study analyzes the Canadian case and find, similarly, that a large plume penetrated the stratosphere by 12 August 2017 and got trapped within a meso-scale anticyclonic structure which travelled across the Atlantic. It then broke into three offsprings that could be followed until mid-October performing three round the world journeys and rising up to 23 km. We analyze the dynamical structure of the vortices produced by these two wildfires and demonstrate how they are maintained by the assimilation of data from instruments measuring the signature of the vortices in the temperature and ozone field. We propose that these vortices can be seen as bubbles of low absolute potential vorticity and smoke carried vertically across the stratification from the troposphere inside the middle stratosphere by their internal heating, against the descending flux of the Brewer-Dobson circulation.

Mapping the Electronic Structure of Polypyrrole with Image-Based Electrochemical Scanning Tunnelling Spectroscopy

Conducting polymers are versatile semiconductors whose applications cover a wide range of devices. Their versatility is due, in addition to other factors, to properties that can be easily modulated according to the intended application. It is therefore important to study and map the electronic structure of these materials to allow for a better correlation between structure and properties. Electrochemical scanning tunnelling spectroscopy (EC-STS) can be a powerful tool to characterize the electronic structure of the semiconductor electrolyte interface. In this work we have used image-based EC-STS (IB-EC-STS) to describe quantitatively the band structure of an electrochemically deposited polypyrrole (PPy) film. IB-EC-STS located the band edge of the polymer’s valence band (VB) at 0.95 V vs. RHE (-5.33 eV in the absolute potential scale) and the intragap polaron states formed when the polymer is oxidised (doped) at 0.46 V vs. RHE (-4.84 eV in the absolute potential scale). The IB-EC-STS data were cross checked with electrochemical impedance spectroscopy (EIS) and Mott-Schottky analysis of the interfacial capacitance. The DOS spectrum obtained from EIS data is consistent with the STS-deduced location of the VB and the polarons.

Mapping the Electronic Structure of Polypyrrole with Image-Based Electrochemical Scanning Tunnelling Spectroscopy

Conducting polymers are versatile semiconductors whose applications cover a wide range of devices. Their versatility is due, in addition to other factors, to properties that can be easily modulated according to the intended application. It is therefore important to study and map the electronic structure of these materials to allow for a better correlation between structure and properties. Electrochemical scanning tunnelling spectroscopy (EC-STS) can be a powerful tool to characterize the electronic structure of the semiconductor electrolyte interface. In this work we have used image-based EC-STS (IB-EC-STS) to describe quantitatively the band structure of an electrochemically deposited polypyrrole (PPy) film. IB-EC-STS located the band edge of the polymer’s valence band (VB) at 0.95 V vs. RHE (-5.33 eV in the absolute potential scale) and the intragap polaron states formed when the polymer is oxidised (doped) at 0.46 V vs. RHE (-4.84 eV in the absolute potential scale). The IB-EC-STS data were cross checked with electrochemical impedance spectroscopy (EIS) and Mott-Schottky analysis of the interfacial capacitance. The DOS spectrum obtained from EIS data is consistent with the STS-deduced location of the VB and the polarons.

Mapping the Electronic Structure of Polypyrrole with Image-Based Electrochemical Scanning Tunnelling Spectroscopy

Conducting polymers are versatile semiconductors whose applications cover a wide range of devices. Their versatility is due, in addition to other factors, to properties that can be easily modulated according to the intended application. It is therefore important to study and map the electronic structure of these materials to allow for a better correlation between structure and properties. Electrochemical scanning tunnelling spectroscopy (EC-STS) can be a powerful tool to characterize the electronic structure of the semiconductor electrolyte interface. In this work we have used image-based EC-STS (IB-EC-STS) to describe quantitatively the band structure of an electrochemically deposited polypyrrole (PPy) film. IB-EC-STS located the band edge of the polymer’s valence band (VB) at 0.95 V vs. RHE (-5.33 eV in the absolute potential scale) and the intragap polaron states formed when the polymer is oxidised (doped) at 0.46 V vs. RHE (-4.84 eV in the absolute potential scale). The IB-EC-STS data were cross checked with electrochemical impedance spectroscopy (EIS) and Mott-Schottky analysis of the interfacial capacitance. The DOS spectrum obtained from EIS data is consistent with the STS-deduced location of the VB and the polarons.

Spatial Illustration of Indicatorson the Example of BiomassPotential for Energy Purposesin the Tabi District

This paper is intended to show the importance of spatial accounting, the practicality ofmapping and illustration. To this end, biomass potential that can be grown on arable lands and the resulting indicators were studied on the example of the Tabi járás (Tabi district) of Hungary. The processed data was projected onto maps for mapping the absolute potential, but also specific indicators such as values per hectare or per capita. The results are plotted in equal intervals and along with natural fractures classification of the data. The results thus obtained emphasize the heterogeneity caused by spatial unevenness. Taking such information into account can improve the efficiency of state interventions, investments, developments and the decentralization of other decisions.

Labor markets of urban agglomerations in Russia

The research is devoted to the current state of the labor market of the largest urban agglomerations in Russia. Based on the belt model of agglomeration (consisting of 3 elements), we consider the indicator of official (formal employment) jobs and the level of wages, as well as their differences with distance from the center. To do this, we use data from the Federal tax service’s tax reports that most fully characterize the state of the labor market and cover a full range of businesses and organizations. On the basis of the balance method (the ratio of supply and demand for labor), the existing disparities in the levels of security and the level of remuneration, an assessment of all agglomerations on the relative and absolute potential for the development of labor migration was carried out. It is shown that there is a strong differentiation of the structure of the labor market in Russian agglomerations. The situation in the metropolis in most is much better than on its periphery, but the possible cases of combination of various indicators up to the inversion where the centre of the agglomeration is inferior to his surroundings and rich in jobs and level of remuneration. Based on a combination of these indicators, 12 agglomerations groups are identified for which the need for a differentiated policy is justified, which is discussed in more detail on the example of 4 polar groups. In conclusion, the author substantiates the need to improve the legal framework for managing the development of the labor market in agglomerations, which does not meet the challenges and needs posed by the current situation.

Method for the accurate prediction of electron transfer potentials using an effective absolute potential

A method to predict electron transfer potentials from first principles using the experimental pKa as reference is shown.

Fabrication and mechanical properties of flaxseed fiber bundle-reinforced polybutylene succinate composites

Flaxseed plants are widely grown globally due to the beneficial seed oil derivatives for human and animal consumption and other industrial uses. However, plentiful flaxseed straws are annually burnt after the harvesting of seeds, lacking utilization of the abundant flaxseed fibers, resulting in wastage of a valuable fiber resource and drastic increase in environmental pollution. In this study, initially the chemical composition and mechanical property of flaxseed fiber bundle were investigated, which resulted as 40.11% cellulose, 28.27% hemi-cellulose, 15.08% lignin, 6.3% pectin, 3.1% wax, and the tensile strength of 1.14 cN/dTex. The surface modification treatment was carried out with concentrations of 10 g/L and 20 g/L sodium hydroxide (NaOH). Later, flaxseed fiber bundles reinforced Polybutylene Succinate (PBS) resin composites were fabricated by thermal compression method. The tensile strength of untreated flaxseed fiber bundle/PBS composites was 78.2 MPa, while the flexural strength of 20 g/L NaOH treated flaxseed fiber bundle/PBS composites showed 84% increment from 26.70 MPa to 49.16 MPa. The scanning electron microscopy (SEM) images revealed significantly rougher surface morphology and stronger interfacial bonding of the alkali treated fiber bundles with matrix. The good mechanical properties observed demonstrated the absolute potential of resultant composites reinforced by flaxseed fiber bundles for utilization in the civil and industrial applications.

Mediator Tail Module Is Required for Tac1-Activated CDR1 Expression and Azole Resistance in Candida albicans

ABSTRACT The human fungal pathogen Candida albicans develops drug resistance after long-term exposure to azole drugs in the treatment of chronic candidiasis. Gain-of-function (GOF) mutations in the transcription factor Tac1 and the consequent expression of its targets, drug efflux pumps Cdr1 and Cdr2, are a common mechanism by which C. albicans acquires fluconazole resistance. The mechanism by which GOF mutations hyperactivate Tac1 is currently unknown. Here, we define a transcriptional activation domain (TAD) at the C terminus of Tac1. GOF mutations within the Tac1 TAD, outside the context of full-length Tac1, generally do not enhance its absolute potential as a transcriptional activator. Negative regulation of the Tac1 TAD by the Tac1 middle region is necessary for the activating effect of GOF mutations or fluphenazine to be realized. We have found that full-length Tac1, when hyperactivated by xenobiotics or GOF mutations, facilitates the recruitment of the Mediator coactivator complex to the CDR1 promoter. Azole resistance and the activation of Tac1 target genes, such as CDR1, are dependent on the Tac1 TAD and subunits of the Mediator tail module. The dependence of different Tac1 target promoters on the Mediator tail module, however, varies widely. Lastly, we show that hyperactivation of Tac1 is correlated with its Mediator-dependent phosphorylation, a potentially useful biomarker for Tac1 hyperactivation. The role of Mediator in events downstream of Tac1 hyperactivation in fluconazole-resistant clinical isolates is complex and provides opportunities and challenges for therapeutic intervention.