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A convex fair partition of a convex polygonal region is defined as a partition on which all regions are convex and have equal area and equal perimeter. In this article we describe an algorithm that finds such fair partition. •The Fair Partitions method finds a fair partition for any given convex polygon and any given number of regions.•Our method relies on two well-known methods: Lloyd's algorithm and the Normal Flow Algorithm.•The method proposed in this article can be used in various contexts and many real-world applications.

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A method to access carbonyl compounds using reductive conditions was evaluated via electrochemical reduction of their corresponding N-benzyloxyphthalimide derivatives (NBOPIs). The mechanism of this originally reported electrochemical reaction was proposed based on DFT calculation and is experimentally confirmed herein, contrasting simulated and experimental cyclic voltammetry data. The reaction scope studied in a preparative scale and using redox sensitive functional groups showed good selectivity and tolerance toward oxidation under the reaction conditions with a moderate to good yield (50-71%). Nevertheless, some restrictions with reducible functional groups, like benzyl-brominated and nitro-aromatic derivatives, were observed. The present approach can be considered a self-sustainable electrochemical catalysis for the synthesis of aromatic carbonylic compounds passing through anion radical intermediates produced by a cathodic reaction.

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Dihydrolevoglucosenone (DLG or Cyrene™) solvent is a green dipolar solvent produced from cellulose waste. Different studies have demonstrated that it can successfully replace dipolar solvents, such as N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA) and N-methylpyrrolidinone (NMP), in a variety of chemical reactions. In this paper, the first application of DLG in organic electrosynthesis is described, with results of its use in the electrochemical reduction of benzophenone derivatives (ca. E = -1.75 V vs. Ag/AgCl), as a greener alternative to other dipolar solvents with environmental concerns. Conductivity measurements show that the solvent presents conductivity and viscosity limitations that can be overcome by using EtOH as a cosolvent. The DLG/EtOH mixture resulted in a convenient solvent to carry out galvanostatic electroreductions of starting materials that exhibit high potential value. Furthermore, the reaction pathway (1e- or 2e-) was found to be dependent on the supporting electrolyte used; TBABF4 favored 2e- reduction to the corresponding alcohol (52-85%), whereas LiClO4 promoted C-C pinacolic coupling (47-70%).

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In this work, we provide electrochemical and spectroscopic evidence of the conducting polymer-heavy metal ion interaction by comparing the electrochemical and spectroscopic behavior (FTIR) of two different conducting polymer-modified electrodes based on 3,4-alkoxythiophenes: 3,4-ethylenedioxythiophene (EDOT) and ortho-xylen-3,4-dioxythiophene (XDOT) during the potentiodynamic stripping of copper. By analyzing the electrochemical and spectroscopic results, it is possible to propose two different copper dissolution processes during the electrochemical stripping process, which depend on the conducting polymer used. With PEDOT matrix, stripping occurs in a two-step pathway, observed as two anodic peaks, involving the formation of the Cu+-PEDOT complex and the subsequent oxidation step of the Cu+ complex to release Cu2+ ions. On the other side, the experiments carried out let us propose the formation of a poorly stable Cu2+-PXDOT complex or a superficial mechanism for the Cu2+ release, characterized by a single stripping signal for this process. Thus, the incorporation of Cu ions into the matrix and the stripping release are intimately related to the chemical structure of the polymer used.

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The ketenimines represent an interesting class of organic intermediates which has undergone a regrowth as a consequence of recent extensions of copper catalyzed azide alkyne cycloaddition (CuAAC) to other synthetic fields. This review summarizes the most recent generation methods of ketinimines from CuAAC reaction, highlighting chemical properties focused to the synthesis of cyclic compounds among others, affording a general outlook towards the development of new biologically active compounds.

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RESUMEN INTRODUCCIÓN: El desarrollo de anticuerpos monoclonales (mAbs) contra el péptido relacionado con el gen de la calcitonina (CGRP) ha determinado una nueva era terapéutica en la profilaxis de migraña, demostrando su efectividad en pacientes con migraña episódica (ME) y migraña crónica (MC), con respuesta desde pacientes naïve hasta refractarios a múltiples medicamentos. La disminución del 50% de los ataques de migraña al mes (DMM) durante los primeros 3 meses de uso es el desenlace aproximado en el 50% de los pacientes que reciben esta terapia. OBJETIVO: Este consenso de la Asociación Colombiana de Neurología (ACN) tiene el objetivo de guiar la selección y uso racional de los mAbs antiCGRP en pacientes con ME y MC. MATERIALES Y MÉTODOS: El comité de cefalea de la ACN mediante la aplicación de la metodología Delphi y discusiones en reuniones posteriores desarrolló un documento en formato de consenso soportado en literatura y recomendaciones de expertos. RESULTADOS: Se obtuvieron respuestas de 14 expertos en cefalea sobre moléculas utilizadas en profilaxis de migraña, analizando su aplicabilidad en situaciones clínicas frecuentes. DISCUSIÓN: Los mAbs antiCGRP han demostrado efectividad con adecuado soporte fisiopatológico, considerando que son moléculas de alto precio en una enfermedad de alta prevalencia, existe la necesidad de guíar la selección del paciente que mejor puede beneficiarse de su administración CONCLUSIONES: Los mAbs antiCGRP están recomendados en pacientes con ME y MC que presentan falla terapéutica a otras moléculas profilácticas.

ABSTRACT INTRODUCTION: The development of monoclonal antibodies (mAbs) against Calcitonin Gene Related Peptide (CGRP) has determined a new therapeutic era in migraine prophylaxis, demonstrating its effectiveness in patients with episodic migraine (EM) and chronic migraine (CM), obtaining a response in naive patients and in those who are refractory to multiple medications. A 50% decrease in migraine attacks per month during the first 3 months of use is the approximate outcome in 50% of patients receiving this therapy. OBJECTIVE: This consensus from the Colombian Association of Neurology (ACN) has the objective of serving as a guide for the rational use of antiCGRP mAbs in patients with EM and CM. METHODS AND MATERIALS: The headache committee through the application of the Delphi methodology and discussions in subsequent meetings, develops this consensus, supported in the published literature and expert recommendations. RESULTS: Fourteen answers from headache experts were received regarding the use of drugs for migraine prophylaxis, analyzing their applicability in frequent clinical situations. DISCUSSION: AntiCGRP mAbs have proved their effectiveness with adequate pathophysiological support, but with a high price in a highly prevalent disease, there is then a need to select the patient who best benefits from this therapy. CONCLUSIONS: AntiCGRP mAbs are recommended in patients with EM and CM that have previously failed to other prophylactic drugs.

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Global energy demand is increasing; thus, emerging renewable energy sources, such as organic solar cells (OSCs), are fundamental to mitigate the negative effects of fuel consumption. Within OSC's advancements, the development of efficient and stable interface materials is essential to achieve high performance, long-term stability, low costs, and broader applicability. Inorganic and nanocarbon-based materials show a suitable work function, tunable optical/electronic properties, stability to the presence of moisture, and facile solution processing, while organic conducting polymers and small molecules have some advantages such as fast and low-cost production, solution process, low energy payback time, light weight, and less adverse environmental impact, making them attractive as hole transporting layers (HTLs) for OSCs. This review looked at the recent progress in metal oxides, metal sulfides, nanocarbon materials, conducting polymers, and small organic molecules as HTLs in OSCs over the past five years. The endeavors in research and technology have optimized the preparation and deposition methods of HTLs. Strategies of doping, composite/hybrid formation, and modifications have also tuned the optical/electrical properties of these materials as HTLs to obtain efficient and stable OSCs. We highlighted the impact of structure, composition, and processing conditions of inorganic and organic materials as HTLs in conventional and inverted OSCs.

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During the last decade several research groups have been developing electrochemical procedures to access highly functionalized organic molecules. Among the most exciting advances, the possibility of using free radical chemistry has attracted the attention of the most important synthetic groups. Nowadays, electrochemical strategies based on these species with a synthetic purpose are published continuously in scientific journals, increasing the alternatives for the synthetic organic chemistry laboratories. Free radicals can be obtained in organic electrochemical reactions; thus, this review reassembles the last decade's (2010-2020) efforts of the electrosynthetic community to generate and take advantage of the C-, O-, and N-centered radicals' reactivity. The electrochemical reactions that occur, as well as the proposed mechanism, are discussed, trying to give clear information about the used conditions and reactivity of these reactive intermediate species.

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SUMMARY INTRODUCTION: Chronic daily headache is a high impact entity in the general population. Although chronic migraine and tension-type headache are the most frequent conditions, it is necessary to consider hemicrania continua and new daily persistent headache as part of the differential diagnoses to perform a correct therapeutic approach. OBJECTIVE: To make recommendations for the treatment of chronic daily headache of primary origin METHODOLOGY: The Colombian Association of Neurology, by consensus and Grade methodology (Grading of recommendations, assessment, development and evaluation), presents the recommendations for the preventive treatment of each of the entities of the daily chronic headache of primary origin group. RESULTS: For the treatment of chronic migraine, the Colombian Association of Neurology recommends onabotulinum toxin A, erenumab, topiramate, flunarizine, amitriptyline, and naratriptan. In chronic tension-type headache the recommended therapeutic options are amitriptyline, imipramine, venlafaxine and mirtazapine. Topiramate, melatonin, and celecoxib for the treatment of hemicrania continua. Options for new daily persistent headache include gabapentin and doxycycline. The recommendations for inpatient treatment of patients with chronic daily headache and the justifications for performing neural blockades as a therapeutic complement are also presented. CONCLUSION: The therapeutic recommendations for the treatment of chronic daily headache based on consensus methodology and Grade System are presented.

RESUMEN INTRODUCCIÓN: La cefalea crónica diaria es una entidad de alto impacto en la población general. Aunque la migraña crónica y la cefalea tipo tensión son las condiciones más frecuentes, es necesario considerar la hemicránea continua y la cefalea diaria persistente de novo como parte de los diagnósticos diferenciales para realizar un enfoque terapéutico correcto. OBJETIVO: Hacer recomendaciones para el tratamiento de la cefalea crónica diaria de origen primario METODOLOGÍA: La Asociación Colombiana de Neurología, mediante consenso y metodología GRADE (Grading of Reccomendations, Assesment, Development and Evaluation), presenta las recomendaciones para el tratamiento preventivo de cada una de las entidades del grupo de la cefalea crónica diaria de origen primario. RESULTADOS: Para el tratamiento de la migraña crónica, la Asociación Colombiana de Neurología recomienda onabotulinum toxina A, erenumab, galcanezumab, fremanezumab, topiramato, flunarizina, amitriptilina y naratriptan. En cefalea tipo tensional crónica las opciones terapéuticas recomendadas son amitriptilina, imipramina, venlafaxina y mirtazapina. Para el tratamiento de la hemicránea continua topiramato, melatonina y celecoxib. Las opciones para cefalea diaria persistente de novo incluyen gabapentin y doxiciclina. Se presentan adicionalmente las recomendaciones para el tratamiento intrahospitalario de los pacientes con cefalea crónica diaria y las justificaciones para la realización de bloqueos neurales como complemento terapéutico. CONCLUSIÓN: se presentan las recomendaciones terapéuticas para el tratamiento de la cefalea crónica diaria basado en metodología de consenso y sistema GRADE.

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Currently, azo dye Carmoisine is an additive that is widely used in the food processing industry sector. However, limited biodegradability in the environment has become a major concern regarding the removal of azo dye. In this study, the degradation of azo dye Carmoisine (acid red 14) in an aqueous solution was studied by using a sequenced process of electro-oxidation-plasma at atmospheric pressure (EO-PAP). Both the efficiency and effectiveness of the process were compared individually. To ascertain the behavior of azo dye Carmoisine over the degradation process, the variations in its physical characteristics were analyzed with a voltage-current relationship, optical emission spectra (OES) and temperature. On the other hand, chemical variables were analyzed by finding out pH, electrical conductivity, absorbance (UV/VIS Spectrophotometry), chemical oxygen demand (COD), cyclic voltammetry (CV), energy consumption and cost. The sequenced process (EO-PAP) increased degradation efficiency, reaching 100% for azo dye Carmoisine (acid red 14) in 60 min. It was observed that the introduction of small quantities of iron metal ions (Fe2+/Fe3+) as catalysts into the plasma process and the hydrogen peroxide formed in plasma electrical discharge led to the formation of larger amounts of hydroxyl radicals, thus promoting a better performance in the degradation of azo dye. This sequenced process increased the decolorization process.