Solubility studies are an essential requirement for the development of more efficient industrial processes. In this context, the use of cosolvents is a relevant strategy in pharmaceutical sciences, especially when dealing with green solvents such as water (W (2)) and Polyethylene glycol 400 (PEG 400 (1)). The objective of this study is to thermodynamically analyze the solubility of isoniazid in {PEG 400 (1) + W (2)} cosolvent mixtures at seven temperatures (288.15 to 318.15 K). The study was conducted by calculating thermodynamic functions from experimental solubility data determined using the flask shaking method, employing UV spectrophotometry as the quantification technique. The dissolution process was shown to be endothermic and entropy-driven. Although maximum solubility would be expected to be achieved in a cosolvent mixture, given that the solubility parameter of isoniazid (30.54 MPa1/2) has an intermediate value between the two pure solvents (PEG 400 ≈ 22.5 MPa1/2; Water ≈47.8 MPa1/2), maximum solubility is achieved in pure PEG 400 and the lowest solubility is achieved in pure water.

Introduction: Fentanyl, a synthetic opioid up to 100 times more potent than morphine, has ignited a global public health crisis. In Colombia, its increasing diversion from the medical system to illicit markets represents an emerging threat that demands in-depth analysis. Purpose: The objective of this research was to conduct a comprehensive analysis of the fentanyl phenomenon in the country, covering its history, current socio-health impact, and the systemic failures that facilitate its spread. Methodology: A qualitative methodology was employed, combining narrative documentary analysis with interviews of key informants directly involved in the legal control and institutional response to the opioid. Results: The results reveal that Colombia is in an early phase, defined by pharmaceutical diversion rather than clandestine production. A complex trafficking network exists, involving both legal and illegal actors, with hospitals and clinics being the primary point of leakage according to 67% of those interviewed. This diversion causes a severe health impact, including deaths by overdose (a link made by 78% of experts), and disproportionately affects at-risk youth (44%) and marginalized communities (33%). Conclusions: The study concludes that this problem is a symptom of deep-seated institutional flaws and social vulnerabilities. It highlights a critical window of opportunity to act, making a comprehensive response that combines public health strategies with the rigorous strengthening of controls imperative to contain the threat and prevent an escalation of the crisis.

BACKGROUND:Solubility is a fundamental physicochemical property in pharmaceutical, chemical and environmental industrial processes. Regarding Triclocarban (TCC), a broad-spectrum antimicrobial, solubility is particularly challenging due to its low aqueous solubility and hydrophobic nature; these challenges can be addressed by some effective techniques such as cosolvency, which allows one to increase the solubility of drugs by several orders of magnitude. This study aims to thermodynamically evaluate the solubility of TCC in cosolvent mixtures of PEG 200 + water at different temperatures. METHODS:Experimental solubility data were determined using the shake-flask followed by UV quantification analysis at saturation methods, and thermodynamic functions of the solution processes were calculated using the Gibbs-van't Hoff-Krug model. RESULTS:The solubility results demonstrate the positive cosolvent effect of PEG 200 on the solubility of TCC, whose solution process is thermodynamically strongly governed by the enthalpy of solution with entropic preference in PEG 200-rich mixtures. CONCLUSIONS:The solubility of TCC is an endothermic, thermo-dependent process. The addition of PEG 200 to the cosolvent mixture favors this process and shows a positive cosolvent effect.

The low water solubility of sulfamethazine (SMT) limits its clinical efficacy, making it crucial to study techniques such as cosolvency to optimize pharmaceutical formulations. This study aimed to thermodynamically evaluate the solubility of SMT in {acetonitrile (MeCN) + ethanol (EtOH)} cosolvent mixtures over a temperature range of 278.15 to 318.15 K in order to understand the molecular interactions that govern this process. SMT solubility in the mixtures was measured using a flask-shaking method. The solid phases were analyzed using differential scanning calorimetry (DSC) to rule out polymorphisms. Using the Gibbs–van’t Hoff–Krug model, we calculated the apparent thermodynamic functions of the solution and mixture from the obtained data. The results showed that solubility increased almost linearly with MeCN fraction and temperature, indicating that MeCN is a more efficient solvent and that the process is endothermic. Thermodynamic analysis revealed that dissolution is an endothermic process with favorable entropy for all compositions. The higher solubility in MeCN is attributed to the lower energetic cost required to form the solute cavity compared to the high energy needed to disrupt the hydrogen bond network of ethanol. This behavior can be explained by an enthalpy–entropy compensation phenomenon. This phenomenon provides an essential physicochemical basis for designing pharmaceutical processes.

Background: Solubility is one of the most important parameters in the research and development processes of the pharmaceutical industry. In this context, cosolubility is one of the most used strategies to improve the solubility of poorly soluble drugs, besides allowing to identify some factors involved in the dissolution process. The aim of this research is to evaluate the solubility of sulfamethazine in acetotinitrile + 1-propanol cosolvent mixtures at 9 temperatures (278.15, 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, 313.15, and 318.15 K); a drug used in human and veterinary therapy and two solvents of great chemical–pharmaceutical interest. Methods: The determination was carried out by the shaking flask method and the drug was quantified by UV/Vis spectrophotometry. Results: The solubility of sulfamethazine increases from pure 1-propanol (solvent in which it reaches its lowest solubility at 278.15 K) to pure acetonitrile (solvent in which it reaches its maximum solubility at 318.15 K), behaving in a logarithmic-linear fashion. Conclusions: The increase in solubility is related to the acid/base character of the cosolvent mixtures and not to the solubility parameter of the mixtures. The dissolution process is endothermic and favored by the solution entropy, and also shows a strong entropic compensation.

Introducción: Las hidroeléctricas son la fuente de energía eléctrica más demandada a nivel mundial después del año 2000. Objetivo: Este artículo identificó los impactos ambientales generados por la construcción y operación de la central hidroeléctrica El Quimbo en el área de influencia en el sur de Colombia desde una perspectiva ex-post. Metodología: El estudio fue de carácter mixto, bajo el método deductivo y descriptivo utilizando técnicas de recolección de información como el análisis documental, el reconocimiento abierto y participativo y la encuesta Delphi. Resultados: En total, se identificaron ochenta y ocho (88) impactos ambientales en los ámbitos físico, biótico y socioeconómico. En la dimensión física, se encontraron aspectos como la disminución del caudal de los ríos y la inundación de terrenos; en la dimensión biótica, se identificaron aspectos como el aumento del desplazamiento de la fauna terrestre y el aumento de la mortalidad de especies nativas de flora y fauna terrestre; y en el campo socioeconómico, se destacaron la disminución del empleo agrícola y el aumento del costo de vida. Conclusiones: Se concluye con la identificación de un mayor número de impactos negativos en la dimensión socioeconómica frente a los impactos en los ámbitos físico y biótico.

Sulfamerazine (SMR) is a drug used as an antibacterial agent in the treatment of some pathologies, such as bronchitis, prostatitis and urinary tract infections. Although this drug was developed in 1945 and, due to its toxicity, was partially displaced by penicillin, due to the current problem of bacterial resistance, compounds such as SMR have regained validity. In this context, the thermodynamic study of SMR in cosolvent mixtures of acetonitrile (MeCN) + ethanol (EtOH) at nine temperatures (278.15–318.15 K) is presented. The solubility of SMR was determined by UV–Vis spectrophotometry, following the guidelines of the shake-flask method. The solubility process was endothermic in all cases; thus, the minimum solubility was reached in pure EtOH at 278.15 K, and the maximum solubility was reached in pure MeCN at 318.15 K. Both the solution process and the mixing process were entropy-driven. On the other hand, the solubility data were modeled by using the van’t Hoff–Yalkowsky–Roseman model, obtaining an overall average relative deviation of 3.9%. In general terms, it can be concluded that the solution process of SMR in {MeCN (1) + EtOH (2)} mixtures is thermodependent, favored by the entropy of the solution and mixture; additionally, the van’t Hoff–Yalkowsky–Roseman model allows very good approximations to be obtained and is a simple model that starts from only four experimental data.

Due to its excellent quality, Colombian cocoa has become a product that has made considerable inroads in the national and international market, increasing its demand and the effects inherent to its production practices. This scope review was carried out following the guidelines of the Joanna Briggs Institute (JBI), which allowed the selection of 72 documents, whose information extraction led to the identification and standardization of the economic, ecological and social impacts of the cocoa sector in the different producing cities of Colombia, of which Santander, Antioquia, Arauca, Huila and Tolima stand out since they generate 70% of the cocoa production at the national level. In the review, a total of 13 social, 25 ecological and 21 economic impacts are clearly observed, which correspond to the most persistent impacts evidenced in the different investigations carried out in this country.

Due to its excellent quality, Colombian cocoa has become a product that has made considerable inroads in the national and international market, increasing its demand and the effects inherent to its production practices. This scope review was carried out following the guidelines of the Joanna Briggs Institute (JBI), which allowed the selection of 72 documents, whose information extraction led to the identification and standardization of the economic, ecological and social impacts of the cocoa sector in the different producing cities of Colombia, of which Santander, Antioquia, Arauca, Huila and Tolima stand out since they generate 70 % of the cocoa production at the national level. In the review, a total of 13 social, 25 ecological and 21 economic impacts are clearly observed, which correspond to the most persistent impacts evidenced in the different investigations carried out in this country.

Solubility is one of the most important physicochemical properties due to its involvement in physiological (bioavailability), industrial (design) and environmental (biotoxicity) processes, and in this regard, cosolvency is one of the best strategies to increase the solubility of poorly soluble drugs in aqueous systems. Thus, the aim of this research is to thermodynamically evaluate the dissolution process of triclocarban (TCC) in cosolvent mixtures of {N-methyl-2-pyrrolidone (NMP) + water (W)} at seven temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15 and 318.15 K). Solubility is determined by UV/vis spectrophotometry using the flask-shaking method. The dissolution process of the TCC is endothermic and strongly dependent on the cosolvent composition, achieving the minimum solubility in pure water and the maximum solubility in NMP. The activity coefficient decreases from pure water to NMP, reaching values less than one, demonstrating the excellent positive cosolvent effect of NMP, which is corroborated by the negative values of the Gibbs energy of transfer. In general terms, the dissolution process is endothermic, and the increase in TCC solubility may be due to the affinity of TCC with NMP, in addition to the water de-structuring capacity of NMP generating a higher number of free water molecules.

Certification programmes are often promoted as a sustainable solution for the negative environmental and socio-economic effects generated by agricultural activities. This scope review assesses the seven most adopted certification programmes in Colombian coffee plantations and their ecological, economic and social impacts. In addition, this scope review characterises the coffee regions where the studies are conducted and the main methodological approaches that are used. The review revealed that the main methodological approach used in the studies is the mixed approach and that the largest number of studies is not conducted in the departments that report the highest coffee production rates. The main certification program assessed in this review is the Rainforest Alliance. However, this study also reports the existence of several gaps caused by multi-certification effects. In total, 87 reports of ecological, economic, and social impacts were identified. Out of the 87 environmental impact reports of the certifications identified in this study, 66 were positive and only 21 were negative.

Las aves, el grupo de vertebrados terrestres más diverso, se caracterizan por su amplia distribución geográfica y espacial en el mundo (Rangel-Salazar y Enríquez, 2015); esto les permite la onformación de relaciones con otros organismos, incluso la especie humana, haciéndolas parte del complejo ciclo de la vida (Banco de la República, 2016). Dicha interactividad puede ser entendida como servicios ecosistémicos que ayudan a la funcionalidad de las comunidades naturales (Thompson, 2006, como se citó en Jordano et al., 2009) y a la supervivencia y buen mantenimiento de los hábitats.

ABSTRACT The thermodynamic analysis and preferential solvation of the solubility of sulphanilamide (SA) in five cosolvent mixtures (ethanol + water; 1,4-dioxane + water, acetonitrile + water, dimethyl-sulphoxide + water, and dimethylsulphoxide + water) are presented. The thermodynamic functions are calculated employing the Gibbs and van´t Hoff equations, and the analysis of preferential solvation is developed by inverse Kirkwood–Buff integrals method. The solubility process is endothermic, with entropic favouring in all cases. Finally, according to the solvation parameter, SA is solvated preferentially by water in more polar mixtures, and in DMF + W, and DMSO + W mixtures it is solvated by organic solvent. In the other mixtures (EtOH + W, DIOX + W, and MeCN + W) the SA is solvated by the organic solvent in intermediate mixtures and by water in the less polar mixtures.

Con el objetivo de identificar el estado actual del conocimiento de la avifauna del departamento del Huila (Colombia), se hizo una selección y recopilación de documentos cuya zona de estudio incluyese regiones de este territorio. Como resultado se obtuvo un total de 957 especies registradas, de las cuales 27 son endémicas, 88 casi endémicas, 96 migratorias, 41 presentan algún grado de amenaza nacional y 35 amenaza global. Además, se reportan 278 especies que incrementan su rango de distribución geográfica para el valle del alto río Magdalena. Las áreas más estudiadas corresponden al valle árido del alto Magdalena, hasta los embalses de Betania y El Quimbo, y la zona rural del municipio de Pitalito, mientras las menos exploradas corresponden a la falda oriental de la cordillera Central y la alta montaña de la cordillera Oriental. Los reportes de este estudio resaltan la importancia del Huila, sobre todo en la ecorregión del bosque seco del valle del Magdalena, como centro de endemismo y en general todo el valle del Magdalena como sector relevante para la conservación de aves en los Andes tropicales. Así, el documento presenta una recopilación de especies que incluye información no publicada en medios de divulgación especializada o científica. Esta compilación permite identificar las áreas menos estudiadas donde se pueden focalizar los esfuerzos de muestreo, así como aquellos sectores con potencial de monitoreo y establecimiento de medidas de conservación.

The solubility of sulfamethazine (SMT) in ethylene glycol (EG) + water (W) cosolvent mixtures was determined at nine temperatures (278.15, 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, 313.15 and 318.15 K) by means of the stirring method. From the solubility data, the thermodynamic functions of solution, transfer and mixing were calculated using the Gibbs and van = t Hoff equations. On the other hand, the preferential solvation parameters of SMT were determined by means of the method of the inverse integrals of Kirkwood Buff (IKBI). In general terms, the solubility of SMT is favored by the increase in temperature and the decrease in the polarity of the cosolvent system, thus the maximum solubility is reached in pure EG at 318.15 K and the minimum in pure water at 278.15 K. Gibbs energy is positive in all cases, with a higher contribution from the energy component (enthalpy of solution). Regarding enthalpy-entropic compensation, the process is driven in all cases by the enthalpy of solution. Finally, SMT is preferentially solvated by water in mixtures with higher polarity and by EG in less polar mixtures. (c) 2021 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

The equilibrium solubility at temperatures from (293.15 to 313.15) K, dissolution thermodynamics and preferential solvation of sulphadiazine (SD) in {acetonitrile (ACN) (1) + water (2)} mixtures is reported. Mole fraction solubility of SD (x(3)) increases when temperature arises and also increases with the ACN proportion increasing. It varies from 4.81 x 10(-6) in neat water to 6.02 x 10(-4) in neat ACN at 298.15 K. Solubility behaviour was adequately correlated by Jouyban-Acree, modified Wilson and non-linear (proposed by Machatha et al.) models and the obtained mean percentage deviations (MPD) are 4.1%, 2.3% and 2.3%, respectively. The comparison of the MPD shows that the prediction using Jouyban-Acree model is more accurate than Jouyban-Acree-Abraham equation for solubility prediction of SD in {ACN (1) + water (2)}. From the variation of solubility with temperature the apparent thermodynamic analysis of dissolution was performed in all the mixtures and neat solvents. Based on the inverse Kirkwood-Buff integrals preferential solvation parameters were calculated. SD is preferentially solvated by water in water-rich mixtures (0.00 x(1) < 0.26) but preferentially solvated by ACN in the interval (0.26 x(1) < 0.65). In ACN-rich mixtures the behaviour is not well defined.

A review was conducted on some focused studies in order to determine the environmental impact caused by coffee-producing farms certified by different Good Agricultural and Socio-Economic Practices systems in different coffee-growing regions. This review shows the most persistent impacts as well as the most particular ones worldwide.

The solubility of methylparaben was determined in acetonitrile + water mixtures at several temperatures (278.15 K to 318.15 K). The solubility curves as a function of acetonitrile ratio showed a maximum at a mass fraction of acetonitrile 0.85 at all temperatures. In all cases, the homogeneous mixture splits into two liquid immiscible phases. The concentration range at which phase separation takes place is 0.35-0.70 in a mass fraction of acetonitrile, showing a clearer separation at higher study temperatures. According to the results of DSC, this phase separation was not related to solid phase changes (polymorphism). The apparent enthalpy of the solution process was a nonlinear function of the acetonitrile ratio, and the solution process of the drug is endothermic and enthalpy determined. Finally, the enthalpy-entropy compensation analysis shows a non-linear behaviour, possibly due to the influence of acetonitrile in the solution process of methylparaben in cosolvent acetonitrile + water mixtures.

In 2016, a total of 23 protected areas in Colombia were classified as areas with ecotourism aptitude; this work describes the conditions in which ecotourism is currently developed and the requirements for its practice; exposes the different environmental, sociocultural and economic impacts generated by ecotourism activities and identifies - under the criteria of a expert groups representing different organizations related to the tourism sector and the Protected Areas - how the certifications of touristic quality and environmental sustainability granted by adoption of NTS-TS STANDARDS and the Environmental Management System under ISO 14001, that in 2015 had impact on the environment of protected areas.

This paper presents the solubility of sulfamethazine (SMT) in the acetonitrile (MeCN) + water (W) cosolvent system at nine temperatures. From the solubility experimental data, the thermodynamic functions of solution, mixing, and transfers are calculated and analyzed using the Perlovich graphical method. On the other hand, an enthalpy-entropy compensation analysis is performed and the preferential solvation parameters are calculated using the Kirkwood-Buff (IKBI) inverse integral method. The result of the performed calculations indicates that the SMT solution process is endothermic with entropic favor, where the addition of MeCN has a positive cosolvent effect between pure water and the mixture with w(1) = 0.90. As for the preferential solvation, the SMT molecule is preferentially surrounded by water in water- and MeCN-rich mixtures, and in intermediate mixtures, the SMT molecule tends to be surrounded by MeCN. (C) 2019 Elsevier B.V. All rights reserved.