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Maleimide and amidine functionalities often appear in medicinal and natural product targets. We describe a catalyst-free, three-component coupling reaction for the synthesis of amidinomaleimides. This one-pot reaction fuses a broad range of secondary amines and aldehydes with azidomaleimides. The conditions are mild, simple, modular, high yielding, and amenable to aqueous solvents. Most reaction products can be sufficiently purified without column chromatography. The synthesis creates complex, multifunctional molecules with four different molecules, including a tripeptide, arrayed around an amidinomaleimide core.

Surfactant monolayers at sea spray aerosol (SSA) surfaces regulate various atmospheric processes including gas transfer, cloud interactions, and radiative properties. Most experimental studies of SSA employ a simplified surfactant mixture of long-chain fatty acids (LCFAs) as a proxy for the sea surface microlayer or SSA surface. However, medium-chain fatty acids (MCFAs) make up nearly 30% of the FA fraction in nascent SSA. Given that LCFA monolayers are easily disrupted upon the introduction of chemical heterogeneity (such as mixed chain lengths), simple FA proxies are unlikely to represent realistic SSA interfaces. Integrating experimental and computational techniques, we characterize the impact that partially soluble MCFAs have on the properties of atmospherically relevant LCFA mixtures. We explore the extent to which the MCFA lauric acid (LA) is surface stabilized by varying acidity, salinity, and monolayer composition. We also discuss the impacts of pH on LCFA-assisted LA retention, where the presence of LCFAs may shift the surface-adsorption equilibria of laurate─the conjugate base─toward higher surface activities. Molecular dynamic simulations suggest a mechanism for the enhanced surface retention of laurate. We conclude that increased FA heterogeneity at SSA surfaces promotes surface activity of soluble FA species, altering monolayer phase behavior and impacting climate-relevant atmospheric processes.

Aposematic organisms rely on their conspicuous appearance to signal that they are defended and unpalatable. Such phenotypes are strongly tied to survival and reproduction. Aposematic colors and patterns are highly variable; however, the genetic, biochemical, and physiological mechanisms producing this conspicuous coloration remain largely unidentified. Here, we identify genes potentially affecting color variation in two color morphs of Ranitomeya imitator: the orange-banded Sauce and the redheaded Varadero morphs. We examine gene expression in black and orange skin patches from the Sauce morph and black and red skin patches from the Varadero morph. We identified genes differentially expressed between skin patches, including those that are involved in melanin synthesis (e.g. mlana, pmel, tyrp1), iridophore development (e.g. paics, ppat, ak1), pteridine synthesis (e.g. gch1, pax3-a, xdh), and carotenoid metabolism (e.g. dgat2, rbp1, scarb2). In addition, using weighted correlation network analysis, we identified the top 50 genes with high connectivity from the most significant network associated with gene expression differences between color morphs. Of these 50 genes, 13 were known to be related to color production (gch1, gmps, gpr143, impdh1, mc1r, pax3-a, pax7, ppat, rab27a, rlbp1, tfec, trpm1, xdh).

This study analyzed the mediating role that implicit theories of intelligence and academic self-efficacy may play in the relationship between psychopathology and mathematical performance. The sample consisted of 838 students from first and second year of high school. A numerical calculation test was applied, followed by psychopathology self-report scales, implicit theories of intelligence, and academic self-efficacy. Serial multiple mediation models were tested. The results showed a complete mediation of the effect of psychopathology on mathematical performance through implicit theories of intelligence and academic self-efficacy. The effect of entity theories of intelligence on mathematical performance was both direct and through academic self-efficacy, whereas the effect of incremental theories of intelligence was only through academic self-efficacy. Identifying the variables that mediate the relationship in question is crucial to develop targeted interventions to prevent the development of a vicious circle between psychopathology and poor school performance.

New technologies are changing the way we see and understand university education, with the advent of new, more flexible organization methods capable of reaching people via class formats like Small Private Online Courses (SPOCs). However, studies which have analyzed these types of courses have focused on their implementation and not on the cognitive and emotional processes of students. Therefore, the present study aims to examine the teacher's influence on emotions, dispositional flow, motivation, and metacognitive strategies among university students. There were 1,347 participants in this study (678 men and 669 women), ranging from 18 to 26 years of age (M = 21.43; SD = 2.64). The results were evaluated using a descriptive statistics analysis, a reliability analysis, and a structural equations model which explains the causal relationships between the study variables. In this sense, autonomy support exerted a positive influence on positive emotions and a negative influence on negative emotions. In contrast, psychological control by the teacher positively influenced negative emotions and negatively influenced positive emotions. Moreover, positive emotions exerted a positive influence on dispositional flow, whereas negative emotions exerted a negative influence on dispositional flow. In addition, dispositional flow exerted a positive influence on autonomous motivation, metacognitive strategies, and academic performance. Finally, autonomous motivation exerted a positive influence on academic performance and metacognitive strategies. These results reveal the influence of emotions, motivation, and perception of SPOCs on the adoption of adaptive habits and academic performance among university students.

Alcohol consumption has profound effects on behavior, such as impaired judgment, addiction or even death. It is estimated that alcohol contributes to around three million deaths worldwide, 13.5% of them in young people with ages between 20 and 39 years. Consequently, it is necessary to raise awareness among college and high school students of the risk related to alcohol drinking. The small nematode "Caenorhabditis elegans" is an animal widely used as a model organism to study nearly all aspects of Biochemistry. It is a powerful tool to test the potential bioactivity and molecular mechanisms of natural compounds and drugs "in vivo." Therefore, it is an interesting topic to include in an undergraduate course of Biotechnology, Biochemistry or Biology students among other scientific vocations. "C. elegans" is also used as a neurobiological model to evaluate substances' neurotoxicity and behavioral effects. The proposed experiment introduces students to the handling of this preclinical model and to the evaluation of behavioral alterations induced by chemicals in scientific research. The effects of different doses of ethanol on "C. elegans" behavior are studied using a versatile chemotaxis assay. This laboratory experiment is suitable for an undergraduate course. The practical session can be used in the global strategies of information and awareness of educational centres to mitigate the impact of alcohol abuse among students, both in formal courses or in Science fairs or exhibitions.

This study analyses a procedure to manufacture mortars with different percentages of ceramic waste as partial replacement for aggregates. The study also examines the physical, chemical and mechanical properties of the new mortars, analysing substitution ratios that range from 10% to 50%. Prior to this, all the materials used in the production of the mortar were characterised using X-ray diffraction (XRD) and fluorescence (XRF). The objective was to determine the similarity between different types of ceramic waste, as well as the differences in the minerology and chemical composition with the aggregate. The results of the study show that it is possible to obtain mortars with lower densities compared to the same product with no recycled content. The product’s characteristics make it ideal for the manufacture of prefabricated components for structural floors for rehabilitation works. Finally, the pieces are used in a real rehabilitation case study, highlightining the structural advantages.