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The supramolecular organization of new fullerene derivatives endowed with peptides as biomolecular templates affords ordered nanofibers of several micrometres length based on hydrogen bonds and π–π interactions. [ABSTRACT FROM AUTHOR]

Strictly speaking, Aristotle did not formulate a theory of the emotions, but we find indications of one in several of his treatise. Many studies about his conception of the emotions lose sight of the fact that the Aristotelian analysis of the passions or emotions in every theoretical context responds to a particular philosophical interest and to a specific problem, and they tend to reduce the Aristotelian concept of pathē to one of its components without taking into account the many approaches to the issue, which offer up a very rich and complex perspective of the passions or emotions. My purpose is to reconstruct the core of the Aristotelian theory of the emotions based in the different approaches to the issue that are dispersed throughout the corpus, and the analysis and discussion of the more current interpretive positions. I analize the different components of the emotions, particularly the physiological processes and sensations of pleasure and pain, as well as diverse states and cognitive processes, and I discuss the main interpretative positions, specially the extreme cognitive perspective of Martha Nusbaum. Lastly, I offer a moderate cognitive interpretation of the Aristotelian theory of the emotions. [ABSTRACT FROM AUTHOR]

El artículo presenta una introducción, en la cual el editor menciona algunos de los temas analizados a lo largo de la publicación, entre los cuales se encuentran la metafísica, la teoría de la acción, la psicología cognitiva y la ética.

In this paper I examine Aristotle's notion of practical necessity in the Nicomachean Ethics. This topic has received little attention in spite of its importance for the understanding of aristotelian practical syllogism. I focus my analysis on the controverted example of akratic reasoning in EN VII, 3, 1147a 26-30, in which Aristotle seems to showcase properties of practical reasoning connected with action. Nevertheless, as I hope to show, the aristotelian approach to this issue is insuficient to support an strong interpretation of practical necessity. [ABSTRACT FROM AUTHOR]

Different approaches to achieve 2D supramolecular polymers, as an alternative to the covalent bottom-up approaches reported for the preparation of 2D materials, are reviewed. The significance of the operation of weak non-covalent forces to induce a lateral growth of a number of self-assembling units is collected. The examples of both thermodynamically and kinetically controlled formation of 2D supramolecular polymers showed in this review demonstrate the utility of this strategy to achieve new 2D materials with biased morphologies (nanosheets, scrolls, porous surfaces) and showing elegant applications like chiral recognition, enantioselective uptake or asymmetric organic transformations. Furthermore, elaborated techniques like seeded or living supramolecular polymerizations have been demonstrated to give rise to complex 2D nanostructures., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Supramolecular chemistry has evolved from the traditional focus on thermodynamic on-pathways to the complex study of kinetic off-pathways, which are strongly dependent on environmental conditions. Moreover, the control over pathway complexity allows nanostructures to be obtained that are inaccessible through spontaneous thermodynamic processes. Herein, we present a family of peptide-based π-extended tetrathiafulvalene (exTTF) molecules that show two self-assembly pathways leading to two distinct J-aggregates, namely metastable (M) and thermodynamic (T), with different spectroscopic, chiroptical, and electrochemical behavior. Moreover, cryo-transmission electron microscopy (cryo-TEM) reveals a different morphology for both aggregates and a direct observation of the morphological transformations from tapes to twisted ribbons., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Chromophore-peptide systems: a study on a series of pentapeptides covalently connected to planar π systems (1 a and 1 b) or to a curved π system (1 c) showed the influence of the concave shape on the efficient chiral transmission at nano- and mesoscales. Control over the hierarchical growth by H bonding, π-π, and solvophobic interactions made possible the efficient generation of electroactive 3D helical fibers., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An extensive study by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) of some first-generation and second-generation lanthanide(III)-cored poly(phenylenevinylene) dendrimers is described. The complexes were obtained by self-assembly of suitably functionalized carboxylate dendrons around the lanthanide ion (La(3+), Er(3+)). Fourier transform infrared (FT-IR) spectroscopy gave reasonable evidence for the proposed structures. However, MS was used to ascertain unequivocally the complex formation. The most reliable results were found in the negative reflector mode, using 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene]malononitrile (DCTB) as matrix. Well-defined and highly resolved base peaks corresponding to negative ions of [Gn(4)La](-) and [Gn(4)Er](-) were found in all cases, with an excellent match between the theoretical and observed isotope distributions. However, the 3:1 stoichiometry used in the synthesis guarantees an empirical formula Gn(3)Ln for the complexes., (2008 John Wiley & Sons, Ltd.)

A series of donor-acceptor arrays (exTTF-oPPE-C60) containing pi-conjugated oligo(phenyleneethynylene) wires (oPPE) of different length between pi-extended tetrathiafulvalene (exTTF) as electron donor and fullerene (C60) as electron acceptor has been prepared by following a convergent synthesis. The key reaction in these approaches is the bromo-iodo selectivity of the Hagihara-Sonogashira reaction and the deprotecting of acetylenes with different silyl groups to afford the corresponding donor-acceptor conjugates in moderate yields. The electronic interactions between the three electroactive species were determined by using UV-visible spectroscopy and cyclic voltammetry. Our studies clearly confirm that, although the C60 units are connected to the exTTF donor through pi-conjugated oPPE frameworks, no significant electronic interactions are observed in the ground state. Theoretical calculations predict how a simple exchange from C=C double bonds (i.e., oligo(p-phenylenevinylene) to C triple chemical bond C triple bonds (i.e., oPPE) in the electron donor-acceptor conjugates considerably alters long-range electron transfer. Photoexcitation of exTTF-oPPE-C60 leads to the following features: a transient photoproduct with maxima at 660 and 1000 nm, which are unambiguously attributed to the photolytically generated radical-ion-pair state, [exTTF*+-oPPE-C60*]. Both charge-separation and charge-recombination processes give rise to a molecular-wire behaviour of the oPPE moiety with an attenuation factor (beta) of (0.2+/-0.05) A(-1).