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The management of phantom limb pain (PLP) is still challenging due to a partial understanding of its neurophysiological mechanisms. Structural neuroimaging features are potential biomarkers. However, only a few studies assessed their correlations with clinical severity and treatment response. This study aims to explore the association between brain gray matter volume (GMV) with phantom limb manifestations severity and PLP improvement after neuromodulatory treatments (transcranial direct current stimulation and mirror therapy). Voxel-based morphometry analyses and functional decoding using a reverse inference term-based meta-analytic approach were used. We included 24 lower limb traumatic amputees with moderate to severe PLP. We found that alterations of cortical GMV were correlated with PLP severity but not with other clinical manifestations. Less PLP severity was associated with larger brain clusters GMV in the non-affected prefrontal, insula (non-affected mid-anterior region), and bilateral thalamus. However, only the insula cluster survived adjustments. Moreover, the reverse inference meta-analytic approach revealed that the found insula cluster is highly functionally connected to the contralateral insula and premotor cortices, and the decoded psychological processes related to this cluster were "rating," "sustained attention," "impulsivity," and "suffering." Moreover, we found that responders to neuromodulatory treatment have higher GMV in somatosensory areas (total volume of S1 and S2) in the affected hemisphere at baseline, compared to non-responders, even after adjustments.Our results suggest an essential role of the non-affected mid-anterior insula as an integrating hub of PLP perception and its severity and thus being a critical network for resting PLP intensity. On the other hand, the sensorimotor gray matter volume seems to be critical to ultimately influence the likelihood of dynamic PLP intensity changes related to a neuromodulatory treatment aimed at sensorimotor cortex modulation. These results point out to the importance in differentiating resting vs. dynamic structural brain correlates associated with PLP control.

The ongoing increase in the number of experimental charge-density studies can be related to both the technological advancements and the wide applicability of the method. Regarding materials science, the understanding of bonding features and their relation to the physical properties of materials can not only provide means to optimize such properties, but also to predict and design new materials with the desired ones. In this tutorial, we describe the steps for a charge-density analysis, emphasizing the most relevant features and briefly discussing the applications of the method.

Copper(II) chemistry has always attracted interest owing to its rich coordination geometry. On the one hand, the variety of geometries that the copper(II) atom can adopt makes it a versatile metal with high applicability. On the other hand, the difficulties in controlling the copper(II) geometry may hinder its use in the design of molecules. To evaluate the use of Hirshfeld surfaces for obtaining information related to coordination geometry in copper(II) compounds, the behaviour of the surfaces generated for the copper(II) centres in different coordination environments is analysed. Structural details of four compounds were retrieved from the Cambridge Structural Database and analysed along with the crystal structure of a new compound, namely chloro-bis(1,10-phenanthroline)copper(II) 2-carboxy-4-nitrobenzoate 4-nitrophthalic acid dihydrate {[CuCl(C12H8N2)2]+(C8H4NO6)−·C8H5NO6·2H2O}, here described. The obtained Hirshfeld surfaces behave differently according to the coordination environment, presenting different shapes and shape-related parameters. Furthermore, the curvature properties and fingerprint plots can be useful for evaluating the differences that might occur in the coordination environment.

This work aims at identifying salient parameters of the Hirshfeld surface of transition-metal centers in coordination compounds able to elucidate the nature of metal–ligand interactions. As an alte...

Properties related to the size and shape of Hirshfeld surfaces provide insight into the nature and strength of interactions among the building blocks of molecular crystals. In this work, we demonstrate that functions derived from the curvatures of the surface at a point, namely, shape index (S) and curvedness (C), as well as the distances from the surface to the nearest external (d e) and internal (d i) nuclei, can be used to help understand metal–ligand interactions in coordination polymers. The crystal structure of catena-poly[[[(1,10-phenanthroline-κ2 N,N′)copper(II)]-μ-4-nitrophthalato-κ2 O 1:O 2] trihydrate], {[Cu(C8H3NO6)(C12H8N2)]·3H2O} n , described here for the first time, was used as a prototypical system for our analysis. Decomposition of the coordination polymer into its metal centre and ligand molecules followed by joint analysis of the Hirshfeld surfaces generated for each part unveil qualitative and semi-quantitative information that cannot be easily obtained either from conventional crystal packing analysis or from Hirshfeld surface analysis of the entire polymeric units. The shape index function S is particularly sensitive to the coordination details and its mapping on the surface of the metallic centre is highly dependent on the nature of the ligand and the coordination bond distance. Correlations are established between the shape of the Hirshfeld surface of the metal and the geometry of the metal–ligand contacts in the crystals. This could be applied not only to estimate limiting coordination distances in metal–organic compounds, but also to help establish structure–property relationships potentially useful for the crystal engineering of such materials.

The Tartaruguito outcrop (Pirapozinho municipality, Presidente Prudente Formation, Bauru Basin) has been considered a Fossil-Lagerstatte due to its exceptional fossil quality and large number of fossils recovered. Despite its historical and paleontological importance, a geochemical composition study of the fossils from this site and their sedimentary matrixes has never been performed. Here, we have analyzed fossil turtle shell fragments and their respective sedimentary matrixes collected at Tartaruguito through Powder X-Ray Diffraction and Infrared Spectroscopy techniques, to determine their geochemical composition and obtain clues regarding the fossil diagenesis processes. The analyses showed that the fossil remains of the side-necked turtle Bauruemys elegans from the Tartaruguito locality are mainly composed of calcite (CaCO3) and hydroxyapatite partially substituted by fluorine (Ca10(PO4)6(OH)2-xFx). The sedimentary matrixes are mostly composed of quartz (SiO2) and calcite, with secondary amounts of feldspar. The presence of calcite on both, fossil and rocky matrix, might indicate that the fossil diagenesis process that occurred at the Tartaruguito locality was permineralization by calcite, especially considering the absence of quartz on the bones of the fossil specimens. Furthermore, the presence of a fluor-hydroxyapatite solid-solution might be a plausible explanation for the quality of fossils recovered in Tartaruguito, due to the better stability of fluorapatite when compared to hydroxyapatite.