12 research outputs found
Cellulolytic and Butyrivibrio fibrisolvens bacteria population density, after supplementing fodder diets (Pennisetum clandestinum)
ABSTRACT
Objective. Determine the population density of cellulolytic bacteria, Butyrivibrio fibrisolvens and the concentration of vaccenic acid, by supplementing diets consisting of kikuyu grass (Pennisetum clandestinum Hoechst. Ex Chiov.) as base ingredient, together with cassava flour and biomass (effluent from ethanol production) in rumen simulator-Rusitec. Materials and methods. Four treatments (T) were evaluated, these were composed as: T1/Control 1: 100% kikuyu grass with a total protein intake of 23.9%, T2: a mixture of 70% kikuyu grass, 20% biomass and 10% cassava flour with a total protein intake of 19.4%; T3/Control 2: 100% kikuyu grass, with a 17.8% protein intake and T4: 70% kikuyu grass, 20% biomass and 10% cassava flour with a 15.3% protein intake. One and two-way variance analysis was made and the Pearson correlation coefficient was determined. Results. An increase was observed in the population density of viable cellulolytic bacteria (CFU/ml) and B. fibrisolvens statistically significant (p<0.005) with treatment T2, in contrast to T1, T3 and T4 treatments. In addition, there was a significant increase in the concentration of vaccenic acid (mg/L) in the ruminal content in Rusitec with the same treatment (T2). Conclusions. Results obtained in this ruminal simulation study are evidence to the benefits of kikuyu grass together with cassava flour and biomass diet implementation on the growth of ruminal cellulolytic and B. fibrisolvens bacteria, as well as on the production of vaccenic acid. The study also suggests the nutritional potential that such supplements could provide to grazing bovine feeding
Antagonistic effect of cyclin-dependent kinases and a calcium-dependent phosphatase on polyglutamine-expanded androgen receptor toxic gain-of-function
: Spinal and bulbar muscular atrophy is caused by polyglutamine (polyQ) expansions in androgen receptor (AR), generating gain-of-function toxicity that may involve phosphorylation. Using cellular and animal models, we investigated what kinases and phosphatases target polyQ-expanded AR, whether polyQ expansions modify AR phosphorylation, and how this contributes to neurodegeneration. Mass spectrometry showed that polyQ expansions preserve native phosphorylation and increase phosphorylation at conserved sites controlling AR stability and transactivation. In small-molecule screening, we identified that CDC25/CDK2 signaling could enhance AR phosphorylation, and the calcium-sensitive phosphatase calcineurin had opposite effects. Pharmacologic and genetic manipulation of these kinases and phosphatases modified polyQ-expanded AR function and toxicity in cells, flies, and mice. Ablation of CDK2 reduced AR phosphorylation in the brainstem and restored expression of Myc and other genes involved in DNA damage, senescence, and apoptosis, indicating that the cell cycle-regulated kinase plays more than a bystander role in SBMA-vulnerable postmitotic cells
Cross-cultural invariance of the Spanish version of the COVID-19 Assessment Scorecard to measure the perception of government actions against COVID-19 in Latin America
Objectives: The present study aimed to evaluate the measurement invariance of a general measure of the perception of governmental responses to COVID-|19 (COVID-SCORE-10) in the general population of 13 Latin American countries. Methods: A total of 5780 individuals from 13 Latin American and Caribbean countries selected by non-probabilistic snowball sampling participated. A confirmatory factor analysis was performed and the alignment method was used to evaluate invariance. Additionally, a graded response model was used for the assessment of item characteristics. Results: The results indicate that there is approximate measurement invariance of the COVID-SCORE-10 among the participating countries. Furthermore, IRT results suggest that the COVID-SCORE-10 measures with good psychometric ability a broad spectrum of the construct assessed, especially around average levels. Comparison of COVID-SCORE-10 scores indicated that participants from Cuba, Uruguay and El Salvador had the most positive perceptions of government actions to address the pandemic. Thus, the underlying construct of perception of government actions was equivalent in all countries. Conclusion: The results show the importance of initially establishing the fundamental measurement properties and MI before inferring the cross-cultural universality of the construct to be measured
Humedales de la Orinoquia (Colombia-Venezuela)
La conservación de la inmensa diversidad biológica de la cuenca del Orinoco depende
de nuestra voluntad y del conocimiento que tengamos de sus ecosistemas acuáticos, hasta hoy apenas descritos, siendo como son, abundantes y variados a lo largo del gradiente altitudinal. Ambientes temporales y permanentes; de aguas quietas, corrientes o torrentosas; blancas, claras o negras; naturales, creados o muy transformados por el hombre, conforman un mosaico heterogéneo que da vida a las alturas paramunas y a las cimas de los tepuyes, a los piedemontes, los Llanos, la Guayana y finalmente al Delta,
en la unión salobre del río Orinoco con el océano Atlántico.
Para el Instituto de Investigación de Recursos Biológicos Alexander von Humboldt
la Orinoquia representa un área prioritaria y de especial interés en sus metas de investigación. Los talleres binacionales 2009-2011, auspiciaron la colaboración
entre ambos países y dieron origen a proyectos como el que hoy presentamos. Un libro que reúne años de trabajo y observación en los humedales de esta cuenca, gracias al aporte de investigadores de Venezuela y Colombia cuyos datos, apuntes y análisis han servido para la identificación y descripción de las grandes regiones del Orinoco, su vegetación acuática y la tipología de sus aguas. Este nuevo volumen de la Serie de Recursos Hidrobiológicos y Pesqueros Continentales, identifica y homologa decenas de ambientes acuáticos o humedales que serán a partir de esta síntesis un valioso punto de referencia, que contribuirá sin duda alguna, al proceso de delimitación de los humedales continentales de Colombia.Bogotá, D. C., ColombiaInstituto de Investigación de Recursos Biológicos Alexander von Humbold
Cross-cultural invariance of the Spanish version of the COVID-19 Assessment Scorecard to measure the perception of government actions against COVID-19 in Latin America
Objectives: The present study aimed to evaluate the measurement invariance of a general measure of the perception of governmental responses to COVID-|19 (COVID-SCORE-10) in the general population of 13 Latin American countries. Methods: A total of 5780 individuals from 13 Latin American and Caribbean countries selected by non-probabilistic snowball sampling participated. A confirmatory factor analysis was performed and the alignment method was used to evaluate invariance. Additionally, a graded response model was used for the assessment of item characteristics. Results: The results indicate that there is approximate measurement invariance of the COVID-SCORE-10 among the participating countries. Furthermore, IRT results suggest that the COVID-SCORE-10 measures with good psychometric ability a broad spectrum of the construct assessed, especially around average levels. Comparison of COVID-SCORE-10 scores indicated that participants from Cuba, Uruguay and El Salvador had the most positive perceptions of government actions to address the pandemic. Thus, the underlying construct of perception of government actions was equivalent in all countries. Conclusion: The results show the importance of initially establishing the fundamental measurement properties and MI before inferring the cross-cultural universality of the construct to be measured.Fil: Caycho Rodríguez, Tomás. Universidad Cientifica del Sur;Fil: Valencia, Pablo D.. Universidad Nacional Autónoma de México; MéxicoFil: Ventura León, José. Universidad Privada del Norte; PerúFil: Carbajal León, Carlos. Universidad Norbert Wiener; PerúFil: Vilca, Lindsey W.. Universidad Norbert Wiener; PerúFil: Reyes Bossio, Mario. Universidad Peruana de Ciencias Aplicadas; PerúFil: Delgado Campusano, Mariel. Universidad Peruana de Ciencias Aplicadas; PerúFil: Yupanqui Lorenzo, Daniel E.. Universidad de Ciencias y Humanidades; PerúFil: Paredes Angeles, Rubí. Universidad Peruana Cayetano Heredia;Fil: Rojas Jara, Claudio. Universidad Católica de Maule; ChileFil: Gallegos de San Vicente, Miguel Omar. Universidad Católica de Maule; Chile. Universidad Nacional de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Pontifícia Universidade Católica de Minas Gerais; BrasilFil: Cervigni, Mauricio Alejandro. Universidad Nacional de Rosario; Argentina. Universidad Adventista del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Martino, Pablo Luis. Universidad Nacional de San Luis. Facultad de Psicología. Departamento Formación Basica. Laboratorio de Ciencias de Comportamiento; Argentina. Universidad Nacional de Rosario. Facultad de Psicología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Polanco Carrasco, Roberto. Cuadernos de Neuropsicología; ChileFil: Palacios, Diego Alejandro. Universidad Mariano Gálvez; GuatemalaFil: Moreta-Herrera, Rodrigo. Pontificia Universidad Católica del Ecuador; EcuadorFil: Samaniego Pinho, Antonio. Universidad Nacional de Asunción; ParaguayFil: Lobos Rivera, Marlon Elías. Universidad Tecnológica de El Salvador; El SalvadorFil: Buschiazzo Figares, Andrés. Instituto Alfred Adler Uruguay; UruguayFil: Puerta Cortés, Diana Ximena. Universidad de Ibagué; ColombiaFil: Corrales Reyes, Ibraín Enrique. Hospital General Universitario Carlos Manuel de Céspedes; CubaFil: Calderón, Raymundo. Colegio Estatal de Psicólogos En Intervención de Jalisco A.c. Guadalajara; MéxicoFil: Arias Gallegos, Walter L.. Universidad Católica San Pablo; PerúFil: Petzold, Olimpia. Lone Star College; Estados UnidosFil: Vergara, Ibeth. Universidad Latina de Panamá; PanamáFil: Vega, Diego. Universidad Latina de Costa Rica; Costa RicaFil: Barria Asenjo, Nicol A.. Universidad de Los Lagos; ChileFil: Schulmeyer, Marion K.. Universidad Privada de Santa Cruz de la Sierra; BoliviaFil: Urrutia Rios, Hassell Tatiana. Asociación Nicaragüense para el desarrollo de la psicología; NicaraguaFil: Lira Lira, Arelly Esther. Asociación Nicaragüense para el desarrollo de la psicología; Nicaragu
Test of invariance of the anomie brief scale with the alignment method in 12 Latin American countries
The Social Anomie Brief Scale (SAS10) is a self-report measure of social anomie against new social standards implemented during the current COVID-19 pandemic. The main objective of this study was to evaluate the invariance of the cross-cultural measurement of the SAS10 in a sample of 12 Latin American countries. Additionally, the difficulty and discrimination characteristics of the items were evaluated using the IRT and social anomie was compared between the participating countries. A total of 4,911 people from 12 Latin American countries (Argentina, Bolivia, Chile, Colombia, Cuba, Ecuador, Guatemala, Mexico, Paraguay, Peru, Uruguay, and Venezuela) selected by non-probabilistic snowball sampling participated. The results indicated that the original two-factor model of the SAS10 shows estimation problems and low fit indices in several countries. However, a model of two related dimensions (behavioral and affective) of nine items (SAS-9) presented adequate fit indices in all countries. This model presents adequate estimation of reliability and approximate cross-cultural measurement invariance. Peru was the country with the highest score in the behavioral dimension of social anomie; while Venezuela and Bolivia presented the highest scores in the affective dimension. Mexico was one of the countries with the lowest anomie scores. The results of the IRT would indicate that the characteristics of the SAS-9 items were appropriate. It is concluded that the SAS-9 has shown good psychometric propertiesUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Instituto de Investigaciones Psicológicas (IIP
Assessment of Obsessive Thoughts About COVID-19 in 7 Latin American Countries: Structure and Measurement Invariance of the Obsession With COVID-19 Scale
The present study aimed to evaluate the measurement invariance of the Obsession
with COVID-19 Scale (OCS) among seven Latin American countries: Bolivia, Brazil,
Cuba, El Salvador, Guatemala, Paraguay, and Uruguay. Although the OCS has been used
in several countries and languages, there is a need for approaches that better integrate
the cross-cultural equivalence of the scale. A total of 3185 people participated in the
study. The results indicated the presence of a unidimensional structure and good
reliability indices for the OCS in each country. The alignmentmethod indicated that the
OCS is an invariant measure of COVID-19 obsession among the populations of seven
Latin American countries. The findings based on IRT analysis indicated that all OCS
items had adequate discrimination and difficulty parameters. The findings contribute to
the understanding of the internal structure of the scale in different countries at the
same time, something that has been pending evaluation.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Instituto de Investigaciones Psicológicas (IIP
Relationship between fear of COVID-19, conspiracy beliefs about vaccines and intention to vaccinate against COVID-19: a cross-national indirect effect model in 13 latin american countries
The present study explored the predictive capacity of fear of COVID-19 on the intention to be vaccinated against COVID-19 and the influence in this relationship of conspiracy beliefs as a possible mediating psychological variable, in 13 Latin American countries. A total of 5779 people recruited through non-probabilistic convenience sampling participated. To collect information, we used the Fear of COVID-19 Scale, Vaccine conspiracy beliefs Scale-COVID-19 and a single item of intention to vaccinate. A full a priori Structural Equation Model was used; whereas, cross-country invariance was performed from increasingly restricted structural models. The results indicated that, fear of COVID-19 positively predicts intention to vaccinate and the presence of conspiracy beliefs about COVID-19 vaccines. The latter negatively predicted intention to vaccinate against COVID-19. Besides, conspiracy beliefs about COVID-19 vaccines had an indirect effect on the relationship between fear of COVID-19 and intention to vaccinate against COVID-19 in the 13 countries assessed. Finally, the cross-national similarities of the mediational model among the 13 participating countries are strongly supported. The study is the first to test a cross-national mediational model across variables in a large number of Latin American countries. However, further studies with other countries in other regions of the world are needed.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Instituto de Investigaciones Psicológicas (IIP
Network Analysis of Posttraumatic Growth Dimensions: A Cross-Sectional Study in People Who Experienced the Death of a Loved One from COVID-19 in 16 Latin American Countries
The present study aimed to apply a network analysis model to provide an exploratory
empirical conceptualization of dynamic networks of posttraumatic growth (PTG)
symptoms in 7,434 people who experienced the death of a loved one from
COVID-19 in 16 Latin American countries. The Post-Traumatic Growth Inventory:
Short Form of Eight Items was used. A non-regularized network with partial correlation
coefficients was estimated through the ggmModSelect algorithm. The network
architecture was analyzed for each country through its local properties and global
properties. The results indicated that the networks differed significantly between
countries. The core dimensions in the networks were relating to others, personal
strength, and life value and opportunities, which were more related dimensions
that reinforce the emergence of PTG in all countries. The findings may be useful
to motivate researchers and mental health professionals to consider the importance
of the individual dimensions of PTG in groups of people who experienced the death
of a loved one from COVID-19 in 16 Latin American countries, as well as their
interrelationships.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Instituto de Investigaciones Psicológicas (IIP
Pandemic Grief and Suicidal Ideation in Latin American Countries: A Network Analysis
This study aimed to characterize the network structure of pandemic grief symptoms and suicidal ideation in 2174 people from eight Latin American countries. Pandemic grief and suicidal ideation were measured using the Pandemic Grief Scale and a single item, respectively. Network analysis provides an in-depth characterization of symptom-symptom interactions within mental disorders. The results indicated that, “desire to die,” “apathy” and “absence of sense of life” are the most central symptoms in a pandemic grief symptom network; therefore, these symptoms could be focal elements for preventive and treatment efforts. Suicidal ideation, the wish to die, and the absence of meaning in life had the strongest relationship. In general, the network structure did not differ among the participating countries. It identifies specific symptoms within the network that may increase the likelihood of their co-occurrence and is useful at the therapeutic level.Revisión por pare