Factors associated with hepatitis B virus infection in indigenous communities of Colombia / Factores asociados con la infección por el virus de la hepatitis B en comunidades indígenas de Colombia.

Introduction. Colombia is home to 2 million indigenous people who live in conditions of poverty and with health deficiencies, making them vulnerable to contracting hepatitis B (HBV). Amazonas has a high virus prevalence, and there are barriers to accessing vaccination; thus, part of the population is susceptible to infection. Objective. To identify factors associated with HBV in Colombian indigenous people. Materials and Methods. A case-control study of people over 18 years from four departments of Colombia. Cases were identified through the national hepatitis B notification registry (2015-2022). Controls were selected and matched to cases (2:1) by age, sex, ethnicity, and department. Sociodemographic characteristics, factors associated with contact with body fluids, cultural practices, and vaccination history were identified by means of a survey. The ethics committee of the Universidad de Antioquia approved the project. Results. Seventy five cases and 150 controls from 13 ethnic groups were surveyed. Amazonas contributed 49% of participants, 83% were women, and the median age of cases was 30 years (IQ range: 27-37). The associated factors were a family history of hepatitis B [adjusted OR: 2.61 (95% CI: 1.09-6.27)] and, in women, the number of pregnancies [adjusted OR: 1.61 (95% CI 1.02- 2.54)]. The vaccination history showed a protective effect, but the association was not significant. Conclusion. Aspects associated with family life and unprotected sexual relations seem to be responsible for the potential transmission of the virus. It was not possible to identify associated cultural practices. Innovative and differential strategies are required for indigenous people to achieve a reduction of HBV.

Introducción. Colombia alberga dos millones de indígenas, que viven en condiciones de pobreza y tienen deficiencias en salud, por lo cual están expuestos a contraer infecciones virales como la hepatitis B. El departamento del Amazonas presenta una gran prevalencia del virus y barreras para acceder a la vacunación; por esto, parte de la población es propensa a la infección. Objetivo. Identificar factores asociados con la infección por el virus de la hepatitis B en indígenas colombianos. Materiales y métodos. Se llevó a cabo un estudio de casos y controles en mayores de 18 años de cuatro departamentos del país. Los casos se identificaron mediante el registro nacional de notificación de hepatitis B (2015-2022). Los controles seleccionados de manera concurrente fueron pareados con los casos por edad, sexo, etnia y departamento. En una encuesta se consignaron las características sociodemográficas, los factores asociados con el contacto con sangre y fluidos, las prácticas socioculturales y los antecedentes de vacunación. El proyecto fue aprobado por Comité de Ética de la Universidad de Antioquia. Resultados. Participaron 75 casos y 150 controles de 13 grupos étnicos. El departamento del Amazonas aportó el 49 % de los participantes (83 % mujeres) con una mediana de edad de 30 años (RIC = 27-37). Los factores asociados con una mayor probabilidad de contraer la infección fueron el antecedente de algún familiar infectado con el virus de la hepatitis B (OR ajustado = 2,61) (IC95%: 1,09-6,27) y número de embarazos en mujeres, (OR ajustado = 1,61) (IC95%: 1,02-2,54). La vacunación mostró un efecto protector sin asociación significativa. Conclusión. Los aspectos asociados con la convivencia familiar y el número de embarazos contribuyen a una potencial transmisión vertical y horizontal del virus. No se identificaron prácticas culturales asociadas. Se requieren estrategias novedosas y diferenciales para reducir la transmisión del virus de la hepatitis B en poblaciones indígenas.

Glycerol valorization using Colombian olivine as a catalyst.

The biodiesel industry currently generates large amounts of crude glycerol that are not marketed, thus accumulating, and causing environmental problems. This study evaluates the catalytic potential of Colombian olivine, using glycerol steam reforming to assess valorization alternatives for this by-product. The analyzed olivine was thermally treated at 1200 °C and reduced at 900 °C, then producing nanometer-sized Fe compounds. The catalyst was characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area, scanning electron microscopy (SEM), temperature-programmed reduction (TPR), and transmission electron microscopy (TEM). Calcined olivine increased glycerol conversion at 600 °C from 43% (without catalyst) to 96% with the formation of liquid-phase products such as aldehydes and carboxylic acids. In addition, syngas with H2/CO ratios of 1.1 and 1.5 was generated at reaction temperatures of 700 °C and 800 °C, respectively, with low CH4 content. Finally, it was established that olivine from Medellín, under the conditions used for glycerol steam reforming, is a viable and interesting alternative to valorize glycerol into gas- or liquid-phase products.

CO Oxidation Catalytic Effects of Intrinsic Surface Defects in Rhombohedral LaMnO3.

There is an ongoing effort to replace rare and expensive noble-element catalysts with more abundant and less expensive transition metal oxides. With this goal in mind, the intrinsic defects of a rhombohedral perovskite-like structure of LaMnO3 and their implications on CO catalytic properties were studied. Surface thermodynamic stability as a function of pressure (P) and temperature (T) were calculated to find the most stable surface under reaction conditions (P=0.2 atm, T=323 K to 673 K). Crystallographic planes (100), (111), (110), and (211) were evaluated and it was found that (110) with MnO2 termination was the most stable under reaction conditions. Adsorption energies of O2 and CO on (110) as well as the effect of intrinsic defects such as Mn and O vacancies were also calculated. It was found that O vacancies favor the interaction of CO on the surface, whereas Mn vacancies can favor the formation of carbonate species.

[Hepatitis B in indigenous people in Latin America: a literature reviewHepatite B em indígenas na América Latina: revisão da literatura]. / Hepatitis B en indígenas de América Latina: una revisión de la literatura.

Objective: Identify publications from 2000 to 2020 on hepatitis B in indigenous people in Latin America, to learn about advances and gaps in this field in the last 20 years. Methods: Exploratory review and systematic evidence review. Documents were organized using Excel and Rayyan® software. Results: We selected 30 of 107 articles found: 17 epidemiological studies, 10 document reviews, 2 clinical studies, and 1 letter to the editor. Brazil was the country with the most publications (50%), most of them with an epidemiological approach. The topic most often addressed was hepatitis B prevalence with 22 publications, followed by 11 studies reporting results of molecular studies of the virus, 7 studies on vaccination, 5 studies on risk factors, and 4 publications with topics such as vertical transmission and studies of social issues. Conclusion: Compared to previous reviews by other authors, we saw greater diversity in topics and research methods; however, conventional epidemiological approaches that focus on measuring prevalence of serological markers still predominate. Thus, there is a need for other types of research focused on sociocultural determinants.

Objetivo: Identificar artigos publicados entre 2000 e 2020 sobre hepatite B em indígenas da América Latina, visando a conhecer as conquistas obtidas nos últimos 20 anos e as lacunas existentes com relação a esta doença. Métodos: Foi realizada uma revisão exploratória da literatura com síntese das evidências. O material obtido foi organizado com o uso de Excel® e Rayyan®. Resultados: De 107 artigos encontrados, 30 foram selecionados ­ 17 estudos epidemiológicos, 10 revisões documentais, 2 estudos clínicos e 1 carta ao editor. O Brasil foi o país com o maior percentual de artigos publicados (50%), na sua maioria estudos com enfoque epidemiológico. As áreas temáticas abordadas foram a prevalência de infecção pelo vírus da hepatite B (22 artigos), estudos moleculares do vírus da hepatite (11 estudos), vacinação (7), fatores de risco (5), e temas como transmissão materno-fetal e aspectos sociais (4). Conclusões: Comparado aos estudos de revisão anteriores conduzidos por outros autores, o presente estudo demonstra uma maior variedade de áreas temáticas e metodologias empregadas. No entanto, ainda predominam enfoques epidemiológicos convencionais com foco na avaliação da prevalência de marcadores sorológicos. São necessárias outras linhas de pesquisas enfocando os determinantes socioculturais.

Hepatitis B en indígenas de América Latina: una revisión de la literatura

[RESUMEN]. Objetivo. Identificar publicaciones realizadas entre los años 2000 y 2020 sobre hepatitis B en indígenas de América Latina, con el fin de conocer avances y vacíos en el tema durante los últimos 20 años. Métodos. Revisión exploratoria y síntesis rápida de la evidencia. El proceso de organización documental se realizó con los programas Excel® y Rayyan®. Resultados. Se seleccionaron 30 de 107 artículos encontrados, 17 corresponden a estudios epidemiológicos, 10 a revisiones documentales, dos estudios clínicos y una carta al editor. Brasil fue el país con más publicaciones (50%), la mayoría con enfoque epidemiológico. La temática más abordada fue la medición de prevalencia de la infección por hepatitis B con 22 publicaciones, le siguieron 11 estudios que informan resultados de estudios moleculares del virus, siete estudios sobre vacunación, cinco estudios sobre factores de riesgo y cuatro publicaciones con temas como la transmisión vertical y estudios sociales. Conclusión. En comparación con revisiones previas realizadas por otros autores, se observa una mayor diversidad en los temas y métodos de investigación utilizados; sin embargo, aún prevalecen los enfoques epidemiológicos convencionales centrados en la medición de la prevalencia de marcadores serológicos. Esto hace necesario encarar otro tipo de investigaciones centradas en los determinantes socioculturales.

[ABSTRACT]. Objective. Identify publications from 2000 to 2020 on hepatitis B in indigenous people in Latin America, to learn about advances and gaps in this field in the last 20 years. Methods. Exploratory review and systematic evidence review. Documents were organized using Excel and Rayyan® software. Results. We selected 30 of 107 articles found: 17 epidemiological studies, 10 document reviews, 2 clinical studies, and 1 letter to the editor. Brazil was the country with the most publications (50%), most of them with an epidemiological approach. The topic most often addressed was hepatitis B prevalence with 22 publications, followed by 11 studies reporting results of molecular studies of the virus, 7 studies on vaccination, 5 studies on risk factors, and 4 publications with topics such as vertical transmission and studies of social issues. Conclusion. Compared to previous reviews by other authors, we saw greater diversity in topics and research methods; however, conventional epidemiological approaches that focus on measuring prevalence of serological markers still predominate. Thus, there is a need for other types of research focused on sociocultural determinants.

[RESUMO]. Objetivo. Identificar artigos publicados entre 2000 e 2020 sobre hepatite B em indígenas da América Latina, visando a conhecer as conquistas obtidas nos últimos 20 anos e as lacunas existentes com relação a esta doença. Métodos. Foi realizada uma revisão exploratória da literatura com síntese das evidências. O material obtido foi organizado com o uso de Excel® e Rayyan®. Resultados. De 107 artigos encontrados, 30 foram selecionados – 17 estudos epidemiológicos, 10 revisões documentais, 2 estudos clínicos e 1 carta ao editor. O Brasil foi o país com o maior percentual de artigos publicados (50%), na sua maioria estudos com enfoque epidemiológico. As áreas temáticas abordadas foram a prevalência de infecção pelo vírus da hepatite B (22 artigos), estudos moleculares do vírus da hepatite (11 estudos), vacinação (7), fatores de risco (5), e temas como transmissão materno-fetal e aspectos sociais (4). Conclusões. Comparado aos estudos de revisão anteriores conduzidos por outros autores, o presente estudo demonstra uma maior variedade de áreas temáticas e metodologias empregadas. No entanto, ainda predominam enfoques epidemiológicos convencionais com foco na avaliação da prevalência de marcadores sorológicos. São necessárias outras linhas de pesquisas enfocando os determinantes socioculturais.

Hepatitis B en indígenas de América Latina: una revisión de la literatura / Hepatitis B in indigenous people in Latin America: a literature review / Hepatite B em indígenas na América Latina: revisão da literatura

RESUMEN Objetivo. Identificar publicaciones realizadas entre los años 2000 y 2020 sobre hepatitis B en indígenas de América Latina, con el fin de conocer avances y vacíos en el tema durante los últimos 20 años. Métodos. Revisión exploratoria y síntesis rápida de la evidencia. El proceso de organización documental se realizó con los programas Excel® y Rayyan®. Resultados. Se seleccionaron 30 de 107 artículos encontrados, 17 corresponden a estudios epidemiológicos, 10 a revisiones documentales, dos estudios clínicos y una carta al editor. Brasil fue el país con más publicaciones (50%), la mayoría con enfoque epidemiológico. La temática más abordada fue la medición de prevalencia de la infección por hepatitis B con 22 publicaciones, le siguieron 11 estudios que informan resultados de estudios moleculares del virus, siete estudios sobre vacunación, cinco estudios sobre factores de riesgo y cuatro publicaciones con temas como la transmisión vertical y estudios sociales. Conclusión. En comparación con revisiones previas realizadas por otros autores, se observa una mayor diversidad en los temas y métodos de investigación utilizados; sin embargo, aún prevalecen los enfoques epidemiológicos convencionales centrados en la medición de la prevalencia de marcadores serológicos. Esto hace necesario encarar otro tipo de investigaciones centradas en los determinantes socioculturales.

ABSTRACT Objective. Identify publications from 2000 to 2020 on hepatitis B in indigenous people in Latin America, to learn about advances and gaps in this field in the last 20 years. Methods. Exploratory review and systematic evidence review. Documents were organized using Excel and Rayyan® software. Results. We selected 30 of 107 articles found: 17 epidemiological studies, 10 document reviews, 2 clinical studies, and 1 letter to the editor. Brazil was the country with the most publications (50%), most of them with an epidemiological approach. The topic most often addressed was hepatitis B prevalence with 22 publications, followed by 11 studies reporting results of molecular studies of the virus, 7 studies on vaccination, 5 studies on risk factors, and 4 publications with topics such as vertical transmission and studies of social issues. Conclusion. Compared to previous reviews by other authors, we saw greater diversity in topics and research methods; however, conventional epidemiological approaches that focus on measuring prevalence of serological markers still predominate. Thus, there is a need for other types of research focused on sociocultural determinants.

RESUMO Objetivo. Identificar artigos publicados entre 2000 e 2020 sobre hepatite B em indígenas da América Latina, visando a conhecer as conquistas obtidas nos últimos 20 anos e as lacunas existentes com relação a esta doença. Métodos. Foi realizada uma revisão exploratória da literatura com síntese das evidências. O material obtido foi organizado com o uso de Excel® e Rayyan®. Resultados. De 107 artigos encontrados, 30 foram selecionados - 17 estudos epidemiológicos, 10 revisões documentais, 2 estudos clínicos e 1 carta ao editor. O Brasil foi o país com o maior percentual de artigos publicados (50%), na sua maioria estudos com enfoque epidemiológico. As áreas temáticas abordadas foram a prevalência de infecção pelo vírus da hepatite B (22 artigos), estudos moleculares do vírus da hepatite (11 estudos), vacinação (7), fatores de risco (5), e temas como transmissão materno-fetal e aspectos sociais (4). Conclusões. Comparado aos estudos de revisão anteriores conduzidos por outros autores, o presente estudo demonstra uma maior variedade de áreas temáticas e metodologias empregadas. No entanto, ainda predominam enfoques epidemiológicos convencionais com foco na avaliação da prevalência de marcadores sorológicos. São necessárias outras linhas de pesquisas enfocando os determinantes socioculturais.

Catalytic Conversion of n-C7 Asphaltenes and Resins II into Hydrogen Using CeO2-Based Nanocatalysts.

This study focuses on evaluating the volumetric hydrogen content in the gaseous mixture released from the steam catalytic gasification of n-C7 asphaltenes and resins II at low temperatures (<230 °C). For this purpose, four nanocatalysts were selected: CeO2, CeO2 functionalized with Ni-Pd, Fe-Pd, and Co-Pd. The catalytic capacity was measured by non-isothermal (from 100 to 600 °C) and isothermal (220 °C) thermogravimetric analyses. The samples show the main decomposition peak between 200 and 230 °C for bi-elemental nanocatalysts and 300 °C for the CeO2 support, leading to reductions up to 50% in comparison with the samples in the absence of nanoparticles. At 220 °C, the conversion of both fractions increases in the order CeO2 < Fe-Pd < Co-Pd < Ni-Pd. Hydrogen release was quantified for the isothermal tests. The hydrogen production agrees with each material's catalytic activity for decomposing both fractions at the evaluated conditions. CeNi1Pd1 showed the highest performance among the other three samples and led to the highest hydrogen production in the effluent gas with values of ~44 vol%. When the samples were heated at higher temperatures (i.e., 230 °C), H2 production increased up to 55 vol% during catalyzed n-C7 asphaltene and resin conversion, indicating an increase of up to 70% in comparison with the non-catalyzed systems at the same temperature conditions.

Data of preparation and evaluation of supramolecular hydrogel based on cellulose for sustained release of therapeutic substances with antimicrobial and wound healing properties.

The data article refers to the paper "supramolecular hydrogel based on cellulose for sustained release of therapeutic substances with antimicrobial and wound healing properties"[1]. The dataset includes the synthesis and characterization of (E)-1,3-bis(4-(allyloxy)phenyl)prop­2-en-1-one (3) (crosslinking agent). Moreover, the multiwall carbon nanotubes (MWCNTs) synthesis and functionalization (MWCNTs-COOH) are described. The formulation obtained by adding multiwalled carbon nanotubes-COOH with the crosslinked cellulose-chalcone hydrogel is abbreviated as MWCNTsCCH, and the same formulation loaded with therapeutic substances (TS) is named MWCNTsCCH-TS. The MWCNTsCCH database such as components and their amounts, swelling degree, thermogravimetric analysis, and cytotoxicity evaluation are depicted. Finally, to elucidate the mechanism of therapeutic substances release, the obtained averages of the release profiles were fitted through mathematical models.

Supramolecular hydrogels based on cellulose for sustained release of therapeutic substances with antimicrobial and wound healing properties.

A multifaceted hydrogel-based formulation was reported. The hydrogel was prepared by crosslinking cellulose and substituted chalcone. Moreover, the formulation was conjugated with carbon nanotubes with the aim of increasing the loading amount of bioactive compounds such as allantoin, dexpanthenol, resveratrol and linezolid. The hydrogel formation was confirmed by swelling tests, FT-IR spectroscopy, thermogravimetric analysis and SEM. The hydrogel showed an improved release rate of therapeutic substances, exhibiting a simultaneous and coordinated release according to the chromatographic studies. The efficacy of drug release was confirmed by wound closure and in vivo wound healing studies that showed promising healing results. The antibacterial assays demonstrated that the sustained release of linezolid tends to be very effective. In conclusion, a multifaceted formulation based on carbon nanotube-containing cellulose-chalcone was developed that can potentially be utilized in treating complex wounds owing to its improved wound healing properties and prevention of potential infections.

Effect of Textural Properties and Surface Chemical Nature of Silica Nanoparticles from Different Silicon Sources on the Viscosity Reduction of Heavy Crude Oil.

The main objective of this study is to evaluate the effect of the textural properties and surface chemical nature of silica nanoparticles obtained from different synthesis routes and silicon precursors, on their interactions with asphaltenes and further viscosity reduction of heavy crude oil (HO). Four different SiO2 nanoparticles were used, namely, commercial fumed silica nanoparticles (CSNs) and three in-house-synthesized nanoparticles (named based on the silicon source) modifying the silicon precursor: sodium silicate (SNSS), tetraethylorthosilicate (TEOS) (SNT), and rice husk (SNRH). The nanomaterials were characterized through dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, N2 physisorption (S BET), atomic force microscopy (AFM), and X-ray photoelectron (XP) spectroscopy (XPS). The adsorption of asphaltenes over the different nanoparticles was evaluated at a concentration of 1000 mg·L-1 in toluene. The asphaltene-nanoparticle interactions are closely related to several textural properties, such as roughness, surface area, and hydrodynamic diameter, as well as the surface chemical nature of the materials. The results in the textural characterization exhibited that the sizes of the nanoparticles from TEM ranged between 6.9 and 11.5 nm. Nevertheless, the standard deviation of the measurements showed that the sizes are statistically similar. Inversely, the hydrodynamic diameter changed, affecting the surface silanol group's availability due to a hindering effect on functional groups as the hydrodynamic size of the material increased. The rheological measurements were performed at a fixed nanoparticle dosage of 1000 mg·L-1 and showed that the trend of the degree of viscosity reduction (DVR) was CSN > SNT > SNSS > SNRH with the highest value yielding at 30%. The results of DVR are in accordance with the nanoparticles' adsorptive capacity as higher values were obtained with the material that leads to a higher amount of adsorbed asphaltenes. Also, the oxygen amount related to silanol groups, estimated by the XPS analysis, showed a direct relation regarding adsorption capacity and further HO viscosity reduction.

Upgrading of Extra-Heavy Crude Oils by Dispersed Injection of NiO-PdO/CeO2±Î´ Nanocatalyst-Based Nanofluids in the Steam.

The main objective of this study is to evaluate the injection of a dispersed nanocatalyst-based nanofluid in a steam stream for in situ upgrading and oil recovery during a steam injection process. The nanocatalyst was selected through adsorption and thermogravimetric experiments. Two nanoparticles were proposed, ceria nanoparticles (CeO2±Î´), with and without functionalization with nickel, and palladium oxides (CeNi0.89Pd1.1). Each one was employed for static tests of adsorption and subsequent decomposition using a model solution composed of n-C7 asphaltenes (A) and resins II (R) separately and for different R:A ratios of 2:8, 1:1, and 8:2. Then, a displacement test consisting of three main stages was successfully developed. At the beginning, steam was injected into the porous media at a temperature of 210 °C, the pore and overburden pressure were fixed at 150 and 800 psi, respectively, and the steam quality was 70%. This was followed by CeNi0.89Pd1.1 dispersed injection in the steam stream. Finally, the treatment was allowed to soak for 12 h, and the steam flooding was carried out again until no more oil production was observed. Among the most relevant results, functionalized nanoparticles achieved higher adsorption of both fractions as well as a lower decomposition temperature. The presence of resins did not affect the amount of asphaltene adsorption over the evaluated materials. The catalytic activity suggests that the increase in resin content promotes a higher conversion in a shorter period of time. Also, for the different steps of the dynamic test, increases of 25% and 42% in oil recovery were obtained for the dispersed injection of the nanofluid in the steam stream and after a soaking time of 12 h, compared with the base curve with only steam injection, respectively. The upgraded crude oil reached an API gravity level of 15.9°, i.e., an increase in 9.0° units in comparison with the untreated extra-heavy crude oil, which represents an increase of 130%. Also, reductions of up to 71% and 85% in the asphaltene content and viscosity were observed.

Dual-Purpose Materials Based on Carbon Xerogel Microspheres (CXMs) for Delayed Release of Cannabidiol (CBD) and Subsequent Aflatoxin Removal.

The main objective of this study is to develop a novel dual-purpose material based on carbon xerogel microspheres (CXMs) that permits the delayed release of cannabidiol (CBD) and the removal of aflatoxin. The CXMs were prepared by the sol-gel method and functionalized with phosphoric acid (CXMP) and melamine (CXMN). The support and the modified materials were characterized by scanning electronic microscopy (SEM), N2 adsorption at -196 °C, X-ray photoelectron spectroscopy (XPS), and zeta potential. For the loading of the cannabidiol (CBD) in the porous samples, batch-mode adsorption experiments at 25 °C were performed, varying the concentration of CBD. The desorption kinetics was performed at two conditions for simulating the gastric (pH of 2.1) and intestinal (pH of 7.4) conditions at 37 °C based on in vitro CBD release. Posteriorly, the samples obtained after desorption were used to study aflatoxin removal, which was evaluated through adsorption experiments at pH = 7.4 and 37 °C. The adsorption isotherms of CBD showed a type I(b) behavior, with the adsorbed uptake being higher for the support than for the modified materials with P and N. Meanwhile, the desorption kinetics of CBD at gastric conditions indicated release values lower than 8%, and the remaining amount was desorbed at pH = 7.4 in three hours until reaching 100% based on the in vitro experiments. The results for aflatoxin showed total removal in less than 30 min for all the materials evaluated. This study opens a broader landscape in which to develop dual-purpose materials for the delayed release of CBD, improving its bioavailability and allowing aflatoxin removal in gastric conditions.

Influence of the Ce4+/Ce3+ Redox-Couple on the Cyclic Regeneration for Adsorptive and Catalytic Performance of NiO-PdO/CeO2±Î´ Nanoparticles for n-C7 Asphaltene Steam Gasification.

The main objective of this study is to evaluate the regenerative effect of functionalized CeO2±Î´ nanoparticles with a mass fraction of 0.89% of NiO and 1.1% of PdO in adsorption and subsequent decomposition of n-C7 asphaltenes in steam gasification processes. During each regeneration cycle, the adsorption capacity and the catalytic activity of the nanoparticles were evaluated. To estimate the adsorption capacity of the nanoparticles, adsorption kinetics were studied at a fixed concentration of n-C7 asphaltenes of 10 mg·L-1 as well as adsorption isotherms at three different temperatures at 25 °C, 55 °C, and 75 °C. To evaluate the catalytic activity, the loss of mass of the nanoparticles was evaluated by isothermal conversions with a thermogravimetric analyzer at 230 °C, 240 °C, and 250 °C, and at non-isothermal conditions involving a heating from 100 °C to 600 °C at a 20 °C·min-1 heating rate. The asphaltenes showed a high affinity for being adsorbed over the nanoparticles surface, due to the nanoparticles-asphaltene interactions are stronger than those that occur between asphaltene-asphaltene, and this was maintained during nine evaluated regeneration cycles as observed in the Henry's constant that increased slightly, with changes of 21%, 26% and 31% for 25 °C, 55 °C and 75 °C. Polanyi's adsorption potential decreases by 2.6% for the same amount adsorbed from the first cycle to the ninth. In addition, the catalytic activity of the nanoparticles did not change significantly, showing that they decompose 100% of the n-C7 asphaltenes in all cycles. However, the small decrease in the adsorption capacity and catalytic activity of the nanoparticles is mainly due to the presence and change in concentration and ratio of certain elements such as oxygen, iron or others at the surface of the nanoparticle as shown by X-ray photoelectron spectroscopy (XPS) analyses. Thermodynamic parameters of adsorption such as Δ H a d s o , Δ S a d s o , and Δ G a d s o and the effective activation energy (Ea) were calculated to compare adsorptive and catalytic performance during each cycle. There is an increase of 9.3% and 2.6% in the case of entropy and enthalpy, respectively, and a decrease of 0.5%, 3.1% and 6.5% for 25 °C, 55 °C and 75 °C respectively for the Gibss free energy from cycle 1 to cycle 9. It was found that these parameters are correlated with the Ce concentration and oxidation state ratios (Ce3+/Ce4+ couple) at the surface.

Optimization of the Load of Transition Metal Oxides (Fe2O3, Co3O4, NiO and/or PdO) onto CeO2 Nanoparticles in Catalytic Steam Decomposition of n-C7 Asphaltenes at Low Temperatures.

The main objective of this work is the catalyst optimization of Fe2O3-, Co3O4-, NiO- and/or PdO- (transition element oxides-TEO) functionalized CeO2 nanoparticles to maximize the conversion of asphaltenes under isothermal conditions at low temperatures (<250 °C) during steam injection processes. Adsorption isotherms and the subsequent steam decomposition process of asphaltenes for evaluating the catalysis were performed through batch adsorption experiments and thermogravimetric analyses coupled to Fourier-transform infrared spectroscopy (FTIR), respectively. The adsorption isotherms and the catalytic behavior were described by the solid-liquid equilibrium (SLE) model and isothermal model, respectively. Initially, three pairs of metal oxide combinations at a mass fraction of 1% of loading of CeNi1Pd1, CeCo1Pd1, and CeFe1Pd1 nanoparticles were evaluated based on the adsorption and catalytic activity, showing better results for the CeNi1Pd1 due to the Lewis acidity changes. Posteriorly, a simplex-centroid mixture design of experiments (SCMD) of three components was employed to optimize the metal oxides concentration (Ni and Pd) onto the CeO2 surface by varying the oxides concentration for mass fractions from 0.0% to 2.0% to maximize the asphaltene conversion at low temperatures. Results showed that by incorporating mono-elemental and bi-elemental oxides onto CeO2 nanoparticles, both adsorption and isothermal conversion of asphaltenes decrease in the order CeNi1Pd1 > CePd2 > CeNi0.66Pd0.66 > CeNi2 > CePd1 > CeNi1 > CeO2. It is worth mentioning that bi-elemental nanoparticles reduced the gasification temperature of asphaltenes in a larger degree than mono-elemental nanoparticles at a fixed amount of adsorbed asphaltenes of 0.02 mg·m-2, confirming the synergistic effects between Pd and Fe, Co, and Ni. Further, optimized nanoparticles (CeNi0.89Pd1.1) have the best performance by obtaining 100% asphaltenes conversion in less than 90 min at 220 °C while reducing 80% the activation energy.

Linkage disequilibrium levels and allele frequency distribution in Blanco Orejinegro and Romosinuano Creole cattle using medium density SNP chip data.

The linkage disequilibrium (LD) between molecular markers affects the accuracy of genome-wide association studies and genomic selection application. High-density genotyping platforms allow identifying the genotype of thousands of single nucleotide polymorphisms (SNPs) distributed throughout the animal genomes, which increases the resolution of LD evaluations. This study evaluated the distribution of minor allele frequencies (MAF) and the level of LD in the Colombian Creole cattle breeds Blanco Orejinegro (BON) and Romosinuano (ROMO) using a medium density SNP panel (BovineSNP50K_v2). The LD decay in these breeds was lower than those reported for other taurine breeds, achieving optimal LD values (r2 ≥ 0.3) up to a distance of 70 kb in BON and 100 kb in ROMO, which is possibly associated with the conservation status of these cattle populations and their effective population size. The average MAF for both breeds was 0.27 ± 0.14 with a higher SNP proportion having high MAF values (≥ 0.3). The LD levels and distribution of allele frequencies found in this study suggest that it is possible to have adequate coverage throughout the genome of these breeds using the BovineSNP50K_v2, capturing the effect of most QTL related with productive traits, and ensuring an adequate prediction capacity in genomic analysis.

GenSeed-HMM: A Tool for Progressive Assembly Using Profile HMMs as Seeds and its Application in Alpavirinae Viral Discovery from Metagenomic Data.

This work reports the development of GenSeed-HMM, a program that implements seed-driven progressive assembly, an approach to reconstruct specific sequences from unassembled data, starting from short nucleotide or protein seed sequences or profile Hidden Markov Models (HMM). The program can use any one of a number of sequence assemblers. Assembly is performed in multiple steps and relatively few reads are used in each cycle, consequently the program demands low computational resources. As a proof-of-concept and to demonstrate the power of HMM-driven progressive assemblies, GenSeed-HMM was applied to metagenomic datasets in the search for diverse ssDNA bacteriophages from the recently described Alpavirinae subfamily. Profile HMMs were built using Alpavirinae-specific regions from multiple sequence alignments (MSA) using either the viral protein 1 (VP1; major capsid protein) or VP4 (genome replication initiation protein). These profile HMMs were used by GenSeed-HMM (running Newbler assembler) as seeds to reconstruct viral genomes from sequencing datasets of human fecal samples. All contigs obtained were annotated and taxonomically classified using similarity searches and phylogenetic analyses. The most specific profile HMM seed enabled the reconstruction of 45 partial or complete Alpavirinae genomic sequences. A comparison with conventional (global) assembly of the same original dataset, using Newbler in a standalone execution, revealed that GenSeed-HMM outperformed global genomic assembly in several metrics employed. This approach is capable of detecting organisms that have not been used in the construction of the profile HMM, which opens up the possibility of diagnosing novel viruses, without previous specific information, constituting a de novo diagnosis. Additional applications include, but are not limited to, the specific assembly of extrachromosomal elements such as plastid and mitochondrial genomes from metagenomic data. Profile HMM seeds can also be used to reconstruct specific protein coding genes for gene diversity studies, and to determine all possible gene variants present in a metagenomic sample. Such surveys could be useful to detect the emergence of drug-resistance variants in sensitive environments such as hospitals and animal production facilities, where antibiotics are regularly used. Finally, GenSeed-HMM can be used as an adjunct for gap closure on assembly finishing projects, by using multiple contig ends as anchored seeds.

Intershell spacing changes in MWCNT induced by metal-CNT interactions.

The intershell spacing in different regions of a multi-walled carbon nanotube (MWCNT) was determined by analysis of high resolution transmission electron (HR-TEM) micrographs. Three general effects can be pointed out, (1) the regular intershell spacing of a CNT is bigger than that in a graphitic carbon because the curvature generates geometrical and electronic deformations which increase repulsion forces between the graphene sheets, (2) when an extra curvature appears, e.g. at the tip of a closed CNT or in a bamboo-like structure, the intershell spacing is expanded due to the extra repulsion caused by the combination of pentagonal and heptagonal rings imbibed in the hexagonal lattice, and (3) when a metal particle interacts with a CNT, the intershell spacing is compressed due to strong metal-CNT interactions.

Estimation of genetic parameters for age at first calving and calving interval in Blanco Orejinegro (BON) breed cattle populations in Colombia / Estimación de parámetros genéticos para edad al primer parto e intervalo entre partos en poblaciones bovinas de la raza Blanco Orejinegro (BON) en Colombia / Estimação de parâmetros genéticos para idade ao primeiro parto e intervalo de partos em populações bovinas da raça Blanco Orejinegro (BON) na Colômbia

Objective: to estimate genetic parameters for age at first calving (AFC) and calving interval (CI) in 22 herds of Blanco Orejinegro cattle in Colombia. Methods: a total of 1,256 records for AFC and 3,803 for CI, obtained between years 1981 and 2010 were analyzed. The (Co) variances components were estimated by a derivative-free restricted maximum likelihood procedure in a bi-trait animal model. Results: average of AFC and CI were 1,104 ± 141 and 487 ± 147 days, respectively. Heritabilities were 0.15 and 0.13 for AFC and CI, respectively, with -0.43 genetic correlation. The herd and year of birth were included as fixed effects for the AFC, while parity number and the covariate age of dam at farrow were analyzed for CI. All the effects had a significant influence over the CI variance. Conclusions: the values obtained for these traits indicate that selection for calving interval and age at first calving may have a relatively low impact, due to the large environmental effect on the variation of both parameters in these breed populations.

Objetivo: estimar los parámetros genéticos de la edad al primer parto (EPP) y del intervalo entre partos (IEP) en 22 poblaciones bovinas de la raza criolla colombiana Blanco Orejinegro. Métodos: se utilizaron 1.256 registros para EPP y 3.803 registros de IEP, obtenidos entre los años 1981 y 2010. Los componentes de (Co) varianza fueron estimados por máxima verosimilitud restringida libre de derivadas con un modelo animal bicaracterístico. Resultados: los promedios de la EPP y del IEP fueron de 1.104 ± 141 y 487 ± 147 días, respectivamente. Las heredabilidades obtenidas en el análisis fueron de 0.15 y 0.13 para EPP e IEP, respectivamente, con una correlación genética de -0.43. Se evaluaron los efectos fijos de año de nacimiento y hato para la EPP, también fue incluido el orden de parto y la covariable edad de la vaca al parto en el análisis del IEP, los cuales todos tuvieron una influencia significativa sobre la variación de este parámetro. Conclusiones: los valores obtenidos para estas características reproductivas en el presente estudio, indican que la selección para intervalo entre parto y edad al primer parto puede tener un efecto relativamente bajo, debido al amplio efecto ambiental sobre la variación de estos dos parámetros en las poblaciones de esta raza.

Objetivo: estimar os parâmetros genéticos de idade ao primeiro parto (EPP) e do intervalo entre partos (IEP) em 22 populações bovinas da raça crioula colombiana Blanco Orejinegro. Métodos: foram utilizadas 1.256 e 3.803 dados para IPP e IEP respectivamente, obtidos entre os anos 1981 e 2010. Os componentes de (Co) variância foram estimados por máxima verossimilhança restrita livre de derivadas com um modelo animal bicaracterístico. Resultados: as médias da EPP e IEP foram 1.104 ± 141 días (36.8 ± 4.7 meses) e 487 ± 147 días (16.2 ± 4.9 meses), respectivamente. As herdabilidades obtidas nas análises foram de 0.15 e 0.13 para EPP e IEP respectivamente, com uma correlação genética de -0.43. Foram incluídos os efeitos fixos de ano de parto e rebanho para EPP, também foi analisado o efeito de ordem de parto e a covariável de idade da vaca ao parto para o IEP. Todos os efeitos incluídos na análise foram significativos sobre a variação do IEP. Conclusões: os valores obtidos no presente estúdio para estas características reprodutivas indicam que a selecção para intervalo entre parto e idade ao primeiro parto podem ter um efeito relativamente baixo, devido ao amplio efeito ambiental sobre a variação destes dois parâmetros nas populações desta raça.

Growth performance of Blanco Orejinegro and Romosinuano bullocks on pasture / Desempeño de toretes de las razas criollas Blanco Orejinegro y Romosinuano en prueba de crecimiento en pastoreo / Teste de desempenho para crescimento de touros jovens das raças Blanco Orejinegro e Romosinuano avaliados a pasto

Objective: to describe the first performance test on Romosinuano (ROMO) and Blanco-Orejinegro (BON) bullocks held at the Nus Experiment Station in northeastern Antioquia (Colombia). Methods: a total of 15 commercial farms participated in the evaluation. The animals were tested under rotational grazing with three planes of nutrition and weighed every 28 days. The measured traits were daily gain, adjusted weight to 540 days, scrotal circumference, morphometric measurements at the end of the test, and carcass traits by ultrasound. Results: a “bull index” was obtained using these characteristics to select the four most outstanding bulls of each breed. Weight gain for the best Blanco-Oreginegro and Romosinuano bulls was higher than 1,000 and 890 g / animal / day, respectively. In addition, their final weight was greater than 340 kg. Animals were genotyped for variants of genes coding for carcass quality and meat, such as calpain (Capn), myostatin (MYO) and diacylglycerol acyltransferase (DGAT1). Conclusions: all Romosinuano individuals had desirable genotype for the CAPN 316 marker, which is associated with increased meat tenderness. On the other hand, Blanco- Orejinegro animals had the desirable genotype for the DGAT1 gene variant, related to fat deposition and fat content in milk. This is the first study that has been reported to select outstanding bulls in Colombian creole cattle breeds to facilitate the evaluation and use of superior genetic material.

Objetivo: el presente trabajo tiene por objeto describir los resultados obtenidos en la primera prueba de desempeño de toretes de las razas bovinas criollas Romosinuano (ROMO) y Blanco Orejinegro (BON), realizada en la Estación Experimental el Nus, en el Nordeste Antioqueño, con la participación de 15 ganaderías comerciales. Métodos: los animales fueron mantenidos en pastoreo rotacional, con tres diferentes planos nutricionales a lo largo de la prueba. Se realizaron pesajes cada 28 días y se evaluó la ganancia diaria de peso, el peso ajustado a los 540 días, la circunferencia escrotal, medidas morfométricas de los animales al final de la prueba, y características de la canal medida por ultrasonido. Resultados: a partir de estas características se definió un índice de toro, para seleccionar los animales sobresalientes (cuatro toretes por cada raza), dichos toros superiores presentaron valores de ganancia de peso en la prueba de desempeño superiores a los 1000 gramos animal día en la raza Blanco Oreginegro y 890 gramos animal día en la raza Romosinuano, además presentaron un peso final superior a los 340 kg. Adicionalmente, los animales fueron genotipados para variantes de genes que codifican para Calpaina (CAPN), Miostatina (MYO) y Diacilglicerol Aciltransferesa (DGAT1) relacionados con la calidad de la canal y la carne. Conclusiones: se encontró que todos los individuos de la raza Romosinuano presentaron el genotipo deseable para el marcador CAPN 316, relacionado con mayor terneza de la carne, por otro lado los animales de la raza Blanco Orejinegro presentaron el genotipo deseable para la variante del gen DGAT1, relacionado con deposición grasa y contenido de grasa en la leche. Este es el primer trabajo que se realiza para seleccionar toros sobresalientes en las razas criollas colombianas y permitirá la evaluación y uso de material genético de calidad superior.

Objetivo: este trabalho tem por objetivo descrever os resultados obtidos no primeiro teste de desempenho de touros jovens das raças crioulas Blanco Orejinegro (BON) e Romosinuano (ROMO), realizada na estação experimental El Nus, localizada no nordeste do departamento de Antioquia. Métodos: o teste teve a participação de 15 fazendas de produtores comerciais. Os animais foram mantidos em pastagem rotacional com três diferentes planos nutricionais ao longo do teste. Realizaram-se pesagens a cada 28 dias e avaliou-se o ganho diário de peso, o peso ajustado aos 540 dias, a circunferência escrotal, medidas morfométricas dos animais ao final do teste, e características da carcaça medidas por ultra-som. A partir destas características definiou-se um índice de touro, para selecionar os bois destacados (quatro touros novos por cada raça). Resultados: os touros superiores apresentaram ganhos de peso no teste de desempenho acima de 1000 gramas por cada animal ao dia na raça Blanco Orejinegro e 890 gramas na raça Romosinuano, além disto, apresentaram um peso final superior aos 340 kg. Adicionalmente, os animais foram genotipados para as variantes genéticas que codificam para a Calpaina (CAPN), miostatina (MYO), e Diacilglicerol Aciltransferase (DGAT1) relacionados com a qualidade da carcaça e da carne. Conclusões: encontrou-se que todos os indivíduos da raça Romosinuano apresentaram o genótipo desejável para o marcador CAPN316, relacionado com maior maciez da carne. De outro lado, os animas da raça Blanco Orejinegro apresentaram o genótipo desejável para a variante do gene DGAT1, relacionado coma deposição de gordura e o conteúdo de gordura no leite. Esta é a primeira pesquisa que se realiza para selecionar touros destacados nas raças crioulas colombianas e permitirá a avaliação e o uso de material genético de qualidade superior.

Effect of polymorphisms in the Slc11a1 coding region on resistance to brucellosis by macrophages in vitro and after challenge in two Bos breeds (Blanco Orejinegro and Zebu).

The resistance/susceptibility of selected cattle breeds to brucellosis was evaluated in an F1 population generated by crossing animals classified as resistant (R) and susceptible (S) (R x R, R x S, S x R, S x S) based on challenges in vitro and in vivo. The association between single nucleotide polymorphisms identified in the coding region of the Slc11a1 gene and resistance/susceptibility was estimated. The trait resistance or susceptibility to brucellosis, evaluated by a challenge in vitro, showed a high heritable component in terms of additive genetic variance (h(2) = 0.54 ± 0.11). In addition, there was a significant association (p < 0.05) between the control of bacterial survival and two polymorphisms (a 3'UTR and SNP4 located in exon 10). The antibody response of animals classified as resistant to infection by Brucella abortus differed significantly (p < 0.05) from that of susceptible animals. However, there was no significant association between single nucleotide polymorphisms located in the Slc11a1 gene and the antibody response stimulated by a challenge in vivo.