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A convenient one-pot method is proposed for the synthesis of 4-aryl-3,4-dihydroquinolin-2(1H)-ones from the monoanilides of malonic acid and aromatic aldehydes. The antiradical activity of the synthesized 4-aryl-3,4-dihydroquinolin-2(1H)-ones was examined (tests on the inhibition of 2,2-di-phenyl-1-picrylhydrazyl and galvinoxyl). It was found that the highest antiradical activity is exhibited by derivatives of syringaldehyde; the activity of the other compounds is moderate or low, however in the 2,2-diphenyl-1-picrylhydrazyl inhibition test it is comparable with or higher than for the widely used antioxidant Ionol. [ABSTRACT FROM AUTHOR]

Suberin, a common biomass processing waste, is a complex biopolymer and a promising source for the biorefinery of chemicals. Six different approaches for the extraction of birch outer bark suberin fatty acids (SFAs) were explored, and their application in grafting the surface of cellulose nanocrystals (CNCs) was investigated. Successful CNC functionalization was controlled with FTIR and NMR analyses. In-depth research allowed us to evaluate the interface of the nanocellulose and polymer matrix. Three structurally distinct SFA-grafted CNCs were integrated into a vegetable oil-based acrylate resin in an ultralow concentration of 0.1 wt %. Five biobased acrylic resin formulations were prepared: without reinforcement, with CNC, and with three distinct SFA-grafted CNCs. Vat photopolymerization (VP) 3D printing was utilized for sample preparation. The effects of grafted CNC components on 3D-printed samples' thermal stability, thermomechanical properties, and wettability were evaluated in detail. CNC functionalization enhanced the interface with the polymer matrix, yielding up to a 2-fold increase in elongation and up to a 2.5-fold increase in strength in tensile and flexural tests compared to the polymeric matrix. The CNC-SFA-modified filler demonstrated performance comparable to, or even better than, petroleum-based chemical modification routes found in the existing literature. This study highlights a promising approach for green functionalization of CNCs and verifies its use in interface enhancement using a biobased acrylate matrix., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Contact restrictions imposed during the COVID-19 pandemic have contributed to the rapid expansion of remote work. With this expansion, new opportunities arise for the typical migrant-sending countries in Central and Eastern Europe to remotely involve their diaspora in their labor market. The aim of this paper is, by using the case study of Latvia, to show the potential of cross-border remote work for alleviating human capital losses caused by emigration. We assess the main obstacles and necessary adjustments in taxes, social benefits, labor market regulation and other areas to facilitate the labor market transition and show what incentives the country can use to become a place of choice for performing remote work for the diaspora. Combining the perspectives of employers, employees and the government, this study sheds new light on the challenges and opportunities related to the rise of remote work for countries suffering from emigration. The comprehensive analysis builds on triangulating secondary data, analysis of policy documents, a survey of employers, as well as a survey and in-depth interviews with cross-border remote workers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Mieriņa and Šūpule.)

Free radicals and oxidants may cause various damages both to the lifeworld and different products. A typical solution for the prophylaxis of oxidation-caused conditions is the usage of various antioxidants. Among them, various classes are found-polyphenols, conjugated polyalkenes, and some sulfur and nitrogen derivatives. Regarding the active site in the molecules, a widely discussed group of compounds are 1,3-dicarbonyl compounds. Among them are natural (e.g., curcumin and pulvinic acids) and synthetic (e.g., 4-hydroxy coumarins, substituted Meldrum's acids) compounds. Herein, information about various compounds containing the 1,3-dicarbonyl moiety is covered, and their antiradical and antioxidant activity, depending on the structure, is discussed.

An efficient protocol for the synthesis of novel lupane triterpenoid-indazolone hybrids with oxime ester linkage has been developed from naturally accessible precursor betulin. For the first time a series of betulonic acid-indazolone hybrids have been synthesized via an acylation of corresponding 6,7-dihydro-1H-indazol-4(5H)-one oximes with betulonic acid chloride. Diastereoselective reduction of the obtained betulonic acid conjugates with NaBH 4 resulted in a formation of betulinic acid-indazolone hybrids in excellent yields. The configuration of the key compounds has been fully established by X-ray and 2D NMR analysis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

This paper explores how unequal resources and social and economic polarization affects the size of social networks and their use to access resources. We argue that individual resource position generates divergent expectations with regard to the impact of polarization on the size of networks on one hand, and their usefulness for accessing resources on the other. Social and economic polarization encourages reliance on informal networks, but those at the bottom of the social structure are forced to rely on more extensive networks than the wealthy to compensate for their isolated and underprivileged position. At the same time, social and economic polarization limits the resources the poor can access through their networks. We provide evidence consistent with these propositions, based on data derived from the International Social Survey Programme 2001 "Social Networks" dataset combined with contextual information on the levels of economic inequality in particular countries along with whether they experienced postcommunism., (Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.)