Genomic Characterization and Functional Description of Beauveria bassiana Isolates from Latin America.

Beauveria bassiana is an entomopathogenic fungus used in agriculture as a biological controller worldwide. Despite being a well-studied organism, there are no genomic studies of B. bassiana isolates from Central American and Caribbean countries. This work characterized the functional potential of eight Neotropical isolates and provided an overview of their genomic characteristics, targeting genes associated with pathogenicity, the production of secondary metabolites, and the identification of CAZYmes as tools for future biotechnological applications. In addition, a comparison between these isolates and reference genomes was performed. Differences were observed according to geographical location and the lineages of the B. bassiana complex to which each isolate belonged.

Draft Genome Sequences of Eight Isolates of Beauveria bassiana of Neotropical Origin.

Beauveria bassiana, a well-known entomopathogenic fungus, has a worldwide distribution; however, genomes of isolates from the Neotropical region are scarce. Here, we report the draft genome sequences of eight B. bassiana isolates from Costa Rica, Puerto Rico, and Honduras.

Identification and phylogenetic analysis of a collection of Beauveria spp. Isolates from Central America and Puerto Rico.

The genus Beauveria comprises economically important entomopathogenic fungi, widely used for biological control in agriculture. Interest in these organisms in Costa Rica prompted surveys and establishment of collections in the past two decades. However, there was neither a formal identification nor a characterization of the isolates. With that purpose, the morphology and genetic variation by microsatellites and partial sequencing of Bloc, TEF-1α and RPB2 regions were studied for 32 isolates of Beauveria, which included 26 from Costa Rica, five from Puerto Rico and one from Honduras. The isolates were identified as B. bassiana (29) and B. caledonica (3). Ninety-three percent of B. bassiana isolates belonged to a monophyletic group of African and Neotropical isolates. A total of 105 alleles were recorded with 11 SSR markers, and the results suggested high diversity within the collection. Mantel tests showed low association between geographic origin and the variation among isolates.

A Combined Metagenomics and Metatranscriptomics Approach to Unravel Costa Rican Cocoa Box Fermentation Processes Reveals Yet Unreported Microbial Species and Functionalities.

Cocoa fermentation is the first step in the post-harvest processing chain of cocoa and is important for the removal of the cocoa pulp surrounding the beans and the development of flavor and color precursors. In the present study, metagenomic and metatranscriptomic sequencing were applied to Costa Rican cocoa fermentation processes to unravel the microbial diversity and assess the function and transcription of their genes, thereby increasing the knowledge of this spontaneous fermentation process. Among 97 genera found in these fermentation processes, the major ones were Acetobacter, Komagataeibacter, Limosilactobacillus, Liquorilactobacillus, Lactiplantibacillus, Leuconostoc, Paucilactobacillus, Hanseniaspora, and Saccharomyces. The most prominent species were Limosilactobacillus fermentum, Liquorilactobacillus cacaonum, and Lactiplantibacillus plantarum among the LAB, Acetobacter pasteurianus and Acetobacter ghanensis among the AAB, and Hanseniaspora opuntiae and Saccharomyces cerevisiae among the yeasts. Consumption of glucose, fructose, and citric acid, and the production of ethanol, lactic acid, acetic acid, and mannitol were linked to the major species through metagenomic binning and the application of metatranscriptomic sequencing. By using this approach, it was also found that Lacp. plantarum consumed mannitol and oxidized lactic acid, that A. pasteurianus degraded oxalate, and that species such as Cellvibrio sp., Pectobacterium spp., and Paucilactobacillus vaccinostercus could contribute to pectin degradation. The data generated and results presented in this study could enhance the ability to select and develop appropriate starter cultures to steer the cocoa fermentation process toward a desired course.

Inoculation and co-inoculation of two monosporic fungi onto surface-sterile blackberry fruits for quantification experiments.

Trichoderma is used as a biocontrol agent against different plant pathogens in different crops. In Costa Rica, Trichoderma isolates from blackberry fruits (Rubus adenotrichos Schltdl.) have shown antagonism in laboratory and field trials against Botrytis cinerea. Quantifying fungal antagonistic activity directly on target organs or target tissues is of interest to estimate the performance of biocontrol agents. However, this is difficult due to the lack of visual manifestations of fungal structures. As part of a larger study to quantify antagonistic activity by quantitative PCR, we detail here a method to isolate and purify each fungus and then inoculate or co-inoculate them onto surface-sterilized blackberry fruits. • A procedure to co-inoculate the surfaces of blackberry fruits with monosporic fungal suspensions for molecular analyses is described. • The protocol described herein was implemented for subsequent qPCR analysis.

A multiplex qPCR TaqMan-assay to detect fungal antagonism between Trichoderma atroviride (Hypocreaceae) and Botrytis cinerea (Sclerotiniaceae) in blackberry fruits using a de novo tef1-α- and an IGS-sequence based probes.

The aim of this study was to design a Trichoderma atroviride-specific qPCR oligo set, evaluate its specificity, and standardize a methodology that quantifies antagonism against Botrytis cinerea in blackberry fruits (Rubus adenotrichos Schltdl.). Primers and probe were designed based on the nuclear translation elongation factor 1-alpha (tef1-α) of T. atroviride. A commercial IGS-based oligo set was used to quantify B. cinerea. The specificity of the designed oligo set, along with ITS-based oligo sets, was assessed using other Trichoderma species and B. cinerea. Multiplex qPCR assays were performed using DNA from B. cinerea, T. atroviride, and blackberries inoculated with these fungi. Assays with the tef1-α oligo set showed high sensitivity and reproducibility. In inoculated fruits, T. atroviride and B. cinerea were quantified simultaneously, including in symptomless tissues. This work standardized a qPCR methodology that specifically targets a T. atroviride isolate. This newly-designed qPCR oligo set could be useful in future biological control programs.

La necesidad de tratamiento ortodóncico desde un perfil bibliométrico / Need of orthodontic treatment from a bibliometric profile

Introducción: las maloclusiones dentarias son anomalías dentomaxilofaciales muy frecuentes en la población mundial. Existe información registrada acerca de la aplicación de índices epidemiológicos para identificar las necesidades de tratamiento ortodóncico. Objetivo: identificar la producción científica donde se apliquen índices de necesidad de tratamiento ortodóncico. Métodos: se realizó un estudio descriptivo y transversal en el periodo de enero a diciembre de 2013. La búsqueda de la información requerida fue realizada en las bases de datos Medline/Pub Med y en SciELO Regional. Los datos fueron registrados de acuerdo con los periodos comprendidos entre 1975-1993, 1994-2003 y por último 2004-2013. El universo de estudio estuvo constituido por 439 resúmenes y/o artículos obtenidos, de los cuales 334 integraron la muestra, al cumplir los criterios de inclusión. Resultados: en el periodo de 1975-1993 se detectaron 24 artículos (7,2 por ciento); durante 1994-2003, 98 (29,3 por ciento) y en los años 2004-2013, 212 (63,5 por ciento). Los trabajos que incluyeron un solo índice fueron 273 (81,7 por ciento), combinados en pares, 49 (14,7 por ciento) y en tres o más, 12 (3,6 por ciento). Conclusiones: en el primer periodo analizado los índices más aplicados fueron: Índice de Tratamiento Prioritario, Índice de Estética Dental y el Índice de Necesidad de Tratamiento Ortodóncico. En el segundo y tercer periodo prevaleció el Índice de Necesidad de Tratamiento Ortodóncico, con incrementos en la aplicación individual de su Componente Estético y el Clínico Dental. En general, este índice fue el más aplicado, tanto solo como en combinaciones, seguido del Índice de Estética Dental(AU)

Introduction: dental malocclusions are dentomaxilofacial anomalies which are found very frequently in the world population. There is registered information about the application of epidemiological indexes to identify the orthodontic treatment needs Objective: to identify the scientific production where the indexes of orthodontic treatment needs are applied.Methods: a cross-sectional and descriptive study was carried out from January to December 2013. The required information was found in Medline, PubMed and Regional Scielo databases. The data were taken in the following periods: 1975-1993, 1994-2003 and 2004-2013. The universe of study consisted of 439 abstracts and/or articles from which 334 were selected for the sample after meeting the inclusion criteria. Results: in the 1975-1993 period, 24 articles (7.2 percent) were identified, 98 articles (29.3 percent) in the 1994-2003 period and 212 (63.5 percent) from 2004 to 2013. The papers comprising just one index amounted to 273 (81.73 percent), two indexes combined in 49 (14.7 percent) and 3 or more in 12 (3.6 pecent).Conclusions: in the first analyzed period, the most used indexes were priority orthodontic treatment index; dental esthetic index, index of orthodontic treatment need. During the second and third periods, the index of orthodontic treatment need prevailed with increased individual application of its esthetic component and the dental clinical component too. In general, this index was the most used alone or in combination, followed by the dental esthetic index(AU)

La necesidad de tratamiento ortodóncico desde un perfil bibliométrico / Need of orthodontic treatment from a bibliometric profile

Introducción: las maloclusiones dentarias son anomalías dentomaxilofaciales muy frecuentes en la población mundial. Existe información registrada acerca de la aplicación de índices epidemiológicos para identificar las necesidades de tratamiento ortodóncico. Objetivo: identificar la producción científica donde se apliquen índices de necesidad de tratamiento ortodóncico. Métodos: se realizó un estudio descriptivo y transversal en el periodo de enero a diciembre de 2013. La búsqueda de la información requerida fue realizada en las bases de datos Medline/Pub Med y en SciELO Regional. Los datos fueron registrados de acuerdo con los periodos comprendidos entre 1975-1993, 1994-2003 y por último 2004-2013. El universo de estudio estuvo constituido por 439 resúmenes y/o artículos obtenidos, de los cuales 334 integraron la muestra, al cumplir los criterios de inclusión. Resultados: en el periodo de 1975-1993 se detectaron 24 artículos (7,2 por ciento); durante 1994-2003, 98 (29,3 por ciento) y en los años 2004-2013, 212 (63,5 por ciento). Los trabajos que incluyeron un solo índice fueron 273 (81,7 por ciento), combinados en pares, 49 (14,7 por ciento) y en tres o más, 12 (3,6 por ciento). Conclusiones: en el primer periodo analizado los índices más aplicados fueron: Índice de Tratamiento Prioritario, Índice de Estética Dental y el Índice de Necesidad de Tratamiento Ortodóncico. En el segundo y tercer periodo prevaleció el Índice de Necesidad de Tratamiento Ortodóncico, con incrementos en la aplicación individual de su Componente Estético y el Clínico Dental. En general, este índice fue el más aplicado, tanto solo como en combinaciones, seguido del Índice de Estética Dental(AU)

Introduction: dental malocclusions are dentomaxilofacial anomalies which are found very frequently in the world population. There is registered information about the application of epidemiological indexes to identify the orthodontic treatment needs. Objective: to identify the scientific production where the indexes of orthodontic treatment needs are applied. Methods: a cross-sectional and descriptive study was carried out from January to December 2013. The required information was found in Medline, PubMed and Regional Scielo databases. The data were taken in the following periods: 1975-1993, 1994-2003 and 2004-2013. The universe of study consisted of 439 abstracts and/or articles from which 334 were selected for the sample after meeting the inclusion criteria. Results: in the 1975-1993 period, 24 articles (7.2 percent) were identified, 98 articles (29.3 percent) in the 1994-2003 period and 212 (63.5 percent) from 2004 to 2013. The papers comprising just one index amounted to 273 (81.73 percent), two indexes combined in 49 (14.7 percent) and 3 or more in 12 (3.6 percent). Conclusions: in the first analyzed period, the most used indexes were priority orthodontic treatment index; dental esthetic index, index of orthodontic treatment need. During the second and third periods, the index of orthodontic treatment need prevailed with increased individual application of its esthetic component and the dental clinical component too. In general, this index was the most used alone or in combination, followed by the dental esthetic index(AU)

Diámetros mesiodistales coronarios de premolares superiores e inferiores en población con oclusión normal. Matanzas / Mesiodistal diameters in upper and lower premolars of population with normal occlusion. Matanzas

Introducción: en el periodo entre la infancia y la adolescencia ocurren variaciones individuales en el crecimiento de los arcos, que hace indispensable el seguimiento y control de cada niño en esta etapa de su vida, donde se requiere realizar mediciones precisas para lograr una predicción exacta de los dientes no erupcionados. Objetivo: determinar el diámetro mesiodistal de premolares superiores e inferiores. Método: se realizó un estudio descriptivo y transversal en adolescentes con oclusión normal, en una muestra de 362 estudiantes, 174 del sexo femenino, y 188 del masculino, con edades de 12, 13 y 14 años, seleccionados mediante muestreo aleatorio simple en las escuelas secundarias básicas de la ciudad de Matanzas. Las mediciones fueron realizadas directamente en la boca desde el punto de contacto mesial hasta distal a nivel de su mayor diámetro con el empleo de un pie de rey. Las variables estudiadas fueron: edad, sexo y diámetro mesiodistal de los premolares superiores e inferiores. Resultados: las medias obtenidas fueron en los dientes posterosuperiores: primeros premolares derechos: 6.9mm, izquierdos: 7,0 mm; segundos premolares derechos: 6,8 mm, izquierdos: 6,9 mm. Los posteroinferiores: primeros premolares derechos: 7,1 mm, izquierdos: 7,0 mm con igual valor en segundos premolares derechos e izquierdos. Conclusiones: los premolares inferiores fueron en su mayoría de mayor tamaño que sus homólogos superiores. Hubo diferencia significativa en cuanto al comportamiento por sexo en los primeros premolares inferiores derechos y segundos premolares inferiores izquierdos. Los premolares en el sexo masculino predominaron en mayor tamaño mesiodistal con respecto al femenino.

Background: The relations between dental arch length and teeth mesioistal size have been studied using several different methods but all of them began from the teeth mesiodistal diameters in different populations with normal occlusion. Aim: Determining mesiodistal diameter of upper and lower premolars. Methods: A cross-sectional descriptive study was carried out in teenagers with normal occlusion, using a sample of 362 students, 174 female, and 188 males, aged 12, 13 and 14 years, chosen in the basic high schools of the city of Matanzas. Measures were taken using a caliper, directly in the mouth from the mesial contact point to the distal one at the level of its bigger diameter. The used variables were age, gender and upper and lower premolar mesiodistal diameter. Results: the measures obtained were, in upper back teeth: first right premolars: 6,9 mm; first left premolars: 7,0 mm; second right premolars: 6,8; second left premolars: 6,9. In lower back teeth: first right premolars: 7,1 mm; first left premolars: 7,0 mm, with the same measure for the second right and left premolars. Conclusions: most of the lower premolars were bigger than their upper homologues. There it was a significant difference between genders in relation to the sizes of the lower right premolars and the second lower left premolars. There it was a predominance of bigger mesiodistal sizes in male premolars than in female ones.

Diámetros mesiodistales coronarios de premolares superiores e inferiores en población con oclusión normal, Matanzas / Mesiodistal diameters in upper and lower premolars of population with normal occlusion, Matanzas

Introducción: en el periodo entre la infancia y la adolescencia ocurren variaciones individuales en el crecimiento de los arcos, que hace indispensable el seguimiento y control de cada niño en esta etapa de su vida, donde se requiere realizar mediciones precisas para lograr una predicción exacta de los dientes no erupcionados.Objetivo: determinar el diámetro mesiodistal de premolares superiores e inferiores. Método: se realizó un estudio descriptivo y transversal en adolescentes con oclusión normal, en una muestra de 362 estudiantes, 174 del sexo femenino, y 188 del masculino, con edades de 12, 13 y 14 años, seleccionados mediante muestreo aleatorio simple en las escuelas secundarias básicas de la ciudad de Matanzas. Las mediciones fueron realizadas directamente en la boca desde el punto de contacto mesial hasta distal a nivel de su mayor diámetro con el empleo de un pie de rey. Las variables estudiadas fueron: edad, sexo y diámetro mesiodistal de los premolares superiores e inferiores.Resultados: las medias obtenidas fueron en los dientes posterosuperiores: primeros premolares derechos: 6.9mm, izquierdos: 7,0 mm; segundos premolares derechos: 6,8 mm, izquierdos: 6,9 mm. Los posteroinferiores: primeros premolares derechos: 7,1 mm, izquierdos: 7,0 mm con igual valor en segundos premolares derechos e izquierdos.Conclusiones: los premolares inferiores fueron en su mayoría de mayor tamaño que sus homólogos superiores. Hubo diferencia significativa en cuanto al comportamiento por sexo en los primeros premolares inferiores derechos y segundos premolares inferiores izquierdos. Los premolares en el sexo masculino predominaron en mayor tamaño mesiodistal con respecto al femenino(AU)

Background: The relations between dental arch length and teeth mesioistal size have been studied using several different methods but all of them began from the teeth mesiodistal diameters in different populations with normal occlusion. Aim: Determining mesiodistal diameter of upper and lower premolars.Methods: A cross-sectional descriptive study was carried out in teenagers with normal occlusion, using a sample of 362 students, 174 female, and 188 males, aged 12, 13 and 14 years, chosen in the basic high schools of the city of Matanzas. Measures were taken using a caliper, directly in the mouth from the mesial contact point to the distal one at the level of its bigger diameter. The used variables were age, gender and upper and lower premolar mesiodistal diameter. Results: the measures obtained were, in upper back teeth: first right premolars: 6,9 mm; first left premolars: 7,0 mm; second right premolars: 6,8; second left premolars: 6,9. In lower back teeth: first right premolars: 7,1 mm; first left premolars: 7,0 mm, with the same measure for the second right and left premolars.Conclusions: most of the lower premolars were bigger than their upper homologues. There it was a significant difference between genders in relation to the sizes of the lower right premolars and the second lower left premolars. There it was a predominance of bigger mesiodistal sizes in male premolars than in female ones(AU)

Discussion of the influence of CO and CH4 in CO2 transport, injection, and storage for CCS technology.

This paper discusses the influence of the noncondensable impurities CO and CH4 on Carbon Capture and Storage (CCS) technology. We calculated and drew conclusions about the impact of both impurities in the CO2 on selected transport, injection, and storage parameters (pipeline pressure drop, storage capacity, etc.), whose analysis is necessary for the safe construction and operation of CO2 pipelines and for the secure long-term geological storage of anthropogenic CO2. To calculate these parameters, it is necessary to acquire data on the volumetric properties and the vapor-liquid equilibrium of the fluid being subjected to CCS. In addition to literature data, we used new experimental data, which are presented here and were obtained for five mixtures of CO2+CO with compositions characteristic of the typical emissions of the E.U. and the U.S.A. Temperatures and pressures are based on relevant CO2 pipeline and geological storage site values. From our experimental results, Peng-Robinson, PC-SAFT, and GERG Equations of State for were validated CO2+CO under the conditions of CCS. We conclude that the concentration of both impurities strongly affects the studied parameters, with CO being the most influential and problematic. The overall result of these negative effects is an increase in the difficulties, risks, and overall costs of CCS.

Diámetro mesiodistal de incisivos y caninos superiores e inferiores. Índices incisivos. Matanzas, 2012 / Mesiodistal diameter of upper and low incisors and canines. Incisal indexes. Matanzas, 2012

El tamaño de los dientes permite establecer un diagnóstico precoz de la falta de espacio para su ubicación futura en el arco dentario y practicar tratamientos interceptivos tempranos. El propósito de este trabajo fue determinar el diámetro mesiodistal de incisivos y caninos superior e inferior, y los índices incisivos superior e inferior, con la finalidad de establecer valores propios de esta población, que contribuyan a elevar la calidad del diagnóstico en Ortodoncia. Fue realizado un estudio descriptivo y transversal en sujetos con oclusión normal, en una muestra de 362 estudiantes: 174 del sexo femenino y 188 del masculino, distribuidos en 143 de doce, 106 de trece y 113 de catorce años, respectivamente, seleccionados en las escuelas secundarias básicas de la ciudad de Matanzas. Las mediciones fueron realizadas por un solo observador, directamente en la boca desde el punto de contacto mesial hasta distal a nivel de su mayor diámetro con el empleo de un pie de rey. Las variables empleadas fueron edad, sexo y diámetro mesiodistal de los dientes. Se determinaron los diámetros mesodistales en los dientes de la arcada superior e inferior con similares tamaños entre ambos lados derechos e izquierdos y los índices incisivos superior (31,20 mm) e inferior (22,70 mm). Se determinó dimorfismo sexual, sustentado en mayor tamaño de los incisivos laterales (P= 0,008), y caninos derechos superiores (P= 0,000) en los varones, así como también en los incisivos laterales derechos (P= 0,001) y caninos derechos (P= 0,000) inferiores en este mismo sexo.

Teeth size allows arriving to a precocious diagnosis of the lack of space for their future location in the dental arch and practicing early interceptive treatments. The aim of this work was finding out the mesiodistal diameter of upper and low incisors and canines, and the upper and low incisal indexes, with the objective of establishing this population own values contributing to the diagnosis quality improvement in Orthodontics. We carried out a cross-sectional descriptive study in people with normal occlusion, in a sample of 362 students: 174 females and 188 males, 143 aged 12 years, 106 aged 13 years and 133 aged 14 years, selected in the secondary schools of the city of Matanzas. Measures were taken by only one person, directly in the mouth, from the mesial contact point to the distal one, at the level of the higher diameter using a Vernier caliper. The used variables were age, gender, and teeth mesial-distal diameter. We determined mesial-distal diameters of the upper and lower arches with similar sizes in both right and left sides, and upper (31,20 mm)and lower (22,70 mm) incisal indexes. We found sexual dimorphism, based on the males´ higher size of the lateral incisors (P= 0,008), and upper right canines (P= 0,000), and also of the right lateral incisors (P= 0,001) and low right canines (P= 0,000).

Diámetro mesiodistal de incisivos y caninos superiores e inferiores. Índices incisivos, Matanzas, 2012 / Mesiodistal diameter of upper and low incisors and canines. Incisal indexes, Matanzas, 2012

El tamaño de los dientes permite establecer un diagnóstico precoz de la falta de espacio para su ubicación futura en el arco dentario y practicar tratamientos interceptivos tempranos. El propósito de este trabajo fue determinar el diámetro mesiodistal de incisivos y caninos superior e inferior, y los índices incisivos superior e inferior, con la finalidad de establecer valores propios de esta población, que contribuyan a elevar la calidad del diagnóstico en Ortodoncia. Fue realizado un estudio descriptivo y transversal en sujetos con oclusión normal, en una muestra de 362 estudiantes: 174 del sexo femenino y 188 del masculino, distribuidos en 143 de doce, 106 de trece y 113 de catorce años, respectivamente, seleccionados en las escuelas secundarias básicas de la ciudad de Matanzas. Las mediciones fueron realizadas por un solo observador, directamente en la boca desde el punto de contacto mesial hasta distal a nivel de su mayor diámetro con el empleo de un pie de rey. Las variables empleadas fueron edad, sexo y diámetro mesiodistal de los dientes. Se determinaron los diámetros mesodistales en los dientes de la arcada superior e inferior con similares tamaños entre ambos lados derechos e izquierdos y los índices incisivos superior (31,20 mm) e inferior (22,70 mm). Se determinó dimorfismo sexual, sustentado en mayor tamaño de los incisivos laterales (P= 0,008), y caninos derechos superiores (P= 0,000) en los varones, así como también en los incisivos laterales derechos (P= 0,001) y caninos derechos (P= 0,000) inferiores en este mismo sexo(AU)

Teeth size allows arriving to a precocious diagnosis of the lack of space for their future location in the dental arch and practicing early interceptive treatments. The aim of this work was finding out the mesiodistal diameter of upper and low incisors and canines, and the upper and low incisal indexes, with the objective of establishing this population own values contributing to the diagnosis quality improvement in Orthodontics. We carried out a cross-sectional descriptive study in people with normal occlusion, in a sample of 362 students: 174 females and 188 males, 143 aged 12 years, 106 aged 13 years and 133 aged 14 years, selected in the secondary schools of the city of Matanzas. Measures were taken by only one person, directly in the mouth, from the mesial contact point to the distal one, at the level of the higher diameter using a Vernier caliper. The used variables were age, gender, and teeth mesial-distal diameter. We determined mesial-distal diameters of the upper and lower arches with similar sizes in both right and left sides, and upper (31,20 mm)and lower (22,70 mm) incisal indexes. We found sexual dimorphism, based on the males´ higher size of the lateral incisors (P= 0,008), and upper right canines (P= 0,000), and also of the right lateral incisors (P= 0,001) and low right canines (P= 0,000)(AU)

Surface tension and density of mixtures of 1,3-dioxolane+alkanols at 298.15 K: analysis under the extended Langmuir model.

Surface tensions (sigma) for [1,3-dioxolane+methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and 1-pentanol] and excess molar volumes (v(E)) for [1,3-dioxolane+methanol, ethanol, 1-propanol, 2-propanol, and 2-butanol] at the temperature 298.15 K and normal atmospheric pressure have been determined as a function of mole fractions. The magnitude of these experimental quantities is discussed in terms of the nature and type of intermolecular interactions in binary mixtures. In order to analyze the surface tension behavior, the extended Langmuir (EL) model was used and the results obtained for the systems containing 1,3-dioxolane were compared with those of other formerly published series: [1,4-dioxane+alkanes] and [1,4-dioxane+alcohols].

Thermodynamic analysis of surface formation of {1,4-dioxane + 1-alkanol} mixtures.

Surface tensions (sigma) for {1,4-dioxane + methanol, ethanol, or 1-propanol} at the temperature 298.15 K and normal atmospheric pressure have been determined as a function of mole fractions. The experimental results have been analyzed using the ideal and Langmuir models and in the light of the well-documented bulk properties of these systems, which reflect hydrogen bonding between the alcohol and 1,4-dioxane molecules. For {1,4-dioxane + ethanol} surface tensions were also measured at other temperatures between 288.15 and 308.15 K, and these data were used to calculate the surface entropy and enthalpy per unit area.