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For this article, the interaction of tetrabutylammonium trifluoromethanesulfonate (TBATFO) with either fumaric (FUM) or maleic (MAL) acid has been investigated. These acids are isomers and can be considered the trans and cis configurations of the same molecular geometry. When TBATFO is mixed with FUM, an eutectic point is obtained for a relative composition of 90-10 (molar ratio), with a melting point of ≈90 °C. If maleic acid is mixed with TBATFO, one obtains an inhomogeneous phase with the retention of a solid portion immersed in a liquid phase, even above 90 °C. DFT calculations helped to model the interaction between the components. It is suggested herein that TBATFO interacts more strongly with FUM than with MAL, due to possible interactions in two different sites for hydrogen bonding (HB) in FUM. In MAL, one of the HB sites is instead retained in the intramolecular interactions; therefore, fewer sites are available for intermolecular interactions. Infrared spectroscopy measurements have confirmed this scenario, in which the hydrogen bonds of the acid molecules are replaced by HB between the acid and the ionic couple: for both kinds of mixtures, the vibration region of the OH bonds is strongly affected by mixing. However, in the case of FUM, the vibrations of the SO3 group of the TFO anion are displaced, while they remain in practically the same frequency position in the case of MAL.

For this article, the interaction of tetrabutylammonium trifluoromethanesulfonate (TBATFO) with either fumaric (FUM) or maleic (MAL) acid has been investigated. These acids are isomers and can be considered the trans and cis configurations of the same molecular geometry. When TBATFO is mixed with FUM, an eutectic point is obtained for a relative composition of 90-10 (molar ratio), with a melting point of ≈90 °C. If maleic acid is mixed with TBATFO, one obtains an inhomogeneous phase with the retention of a solid portion immersed in a liquid phase, even above 90 °C. DFT calculations helped to model the interaction between the components. It is suggested herein that TBATFO interacts more strongly with FUM than with MAL, due to possible interactions in two different sites for hydrogen bonding (HB) in FUM. In MAL, one of the HB sites is instead retained in the intramolecular interactions; therefore, fewer sites are available for intermolecular interactions. Infrared spectroscopy measurements have confirmed this scenario, in which the hydrogen bonds of the acid molecules are replaced by HB between the acid and the ionic couple: for both kinds of mixtures, the vibration region of the OH bonds is strongly affected by mixing. However, in the case of FUM, the vibrations of the SO3 group of the TFO anion are displaced, while they remain in practically the same frequency position in the case of MAL. [ABSTRACT FROM AUTHOR]

Abstract Background Non-painful diagnostic procedures require an inactive state for a prolonged time, so that sedation is often needed in younger children to perform the procedures. Our standard of care in this setting consists of the association between oral midazolam (0.5 mg/kg) and intranasal dexmedetomidine (4 mcg/kg). One of the limits of this approach is that the onset of action is quite delayed (up to 55 min) and poorly predictable. We chose to compare this association with intranasal-ketamine and intranasal-dexmedetomidine. Methods This is a “pre-post” study. The study population included the first forty children receiving sedation with the “new” combination intranasal ketamine (3 mg/kg) and intranasal dexmedetomidine (4 mcg/kg) compared to a historical cohort including the last forty children receiving sedation with our standard of care combination of intranasal dexmedetomidine (4mcg/kg) and oral midazolam (0,5 mg/kg). Results The association intranasal dexmedetomidine and intranasal ketamine allowed for a significantly shorter sedation induction time than the combination intranasal dexmedetomidine and oral midazolam (13,5 min versus 35 min). Both group’s cumulative data showed a correlation between age and sedation effectiveness, with younger children presenting a higher success rate and shorter induction time (p 0,001). Conclusions: This study suggests that the ketamine and dexmedetomidine intranasal association may have a shorter onset of action when compared to intranasal dexmedetomidine and oral midazolam.

The current level of evidence for immunotherapy in previously untreated microsatellite unstable metastatic colorectal cancer is based on recent pieces of evidence of few studies that demonstrated durable response and clinical benefit, in terms of objective response rate, disease control rate, and progression-free survival in this subgroup of patients. On the basis of combinatorial immunotherapy with nivolumab plus ipilimumab, we report the exceptional case of a complete pathological response in a 21-year-old woman presenting a clinically aggressive stage IV colorectal cancer with massive nodal and liver involvement. Extensive molecular analyses based on whole genome next-generation DNA sequencing, RNA sequencing, fluorescent multiplex immunohistochemistry, and flow cytometry provided a detailed description of tumoral and immunological characteristics of this noteworthy clinical case.

Because of scale effects, idea-based growth models imply that larger countries should be much richer than smaller ones. New trade models share the same counterfactual feature. In fact, new trade models exhibit other counterfactual implications associated with scale effects: import shares decrease and relative income levels increase too steeply with country size. We argue that these implications are largely a result of the standard assumption that countries are fully integrated domestically. We depart from this assumption by treating countries as collections of regions that face positive costs to trade among themselves. The resulting model is largely consistent with the data.

Carbon capture and sequestration are the major applied techniques for mitigating CO2 emission. The marked affinity of carbon dioxide to react with amino groups is well known, and the amine scrubbing process is the most widespread technology. Among various compounds and solutions containing amine groups, in biodegradability and biocompatibility perspectives, amino acid ionic liquids (AAILs) are a very promising class of materials having good CO2 absorption capacity. The reaction of amines with CO2 follows a multi-step mechanism where the initial pathway is the formation of the C−N bond between the NH2 group and CO2. The added product has a zwitterionic character and can rearrange to give a carbamic derivative. These steps of the mechanism have been investigated in the present study by quantum mechanical methods by considering three ILs where amino acid anions are coupled with choline cations. Glycinate, L-phenylalanilate and L-prolinate anions have been compared with the aim of examining if different local structural properties of the amine group can affect some fundamental steps of the CO2 absorption mechanism. All reaction pathways have been studied by DFT methods considering, first, isolated anions in a vacuum as well as in a liquid continuum environment. Subsequently, the role of specific interactions of the anion with a choline cation has been investigated, analyzing the mechanism of the amine–CO2 reaction, including different coupling anion–cation structures. The overall reaction is exothermic for the three anions in all models adopted; however, the presence of the solvent, described by a continuum medium as well as by models, including specific cation- -anion interactions, modifies the values of the reaction energies of each step. In particular, both reaction steps, the addition of CO2 to form the zwitterionic complex and its subsequent rearrangement, are affected by the presence of the solvent. The reaction enthalpies for the three systems are indeed found comparable in the models, including solvent effects.

The role of percutaneous tumour biopsies had gain importance in the management of renal cell carcinoma to provide diagnostic specimen for the patients with metastatic disease that could benefit a systemic treatment. Among the possible complications of this procedure, however, there is the risk of tumoral cells seeding along the biopsy’s tract; this complication, albeit being reported as anecdotal, could have devastating effects. Here we report a case of a young male who developed subcutaneous chest metastasis of renal cell carcinoma after a biopsy of a lung nodule. We subsequently reviewed other cases reported in literature