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Estimates, trends, and drivers of the global burden of type 2 diabetes attributable to PM2·5 air pollution, 1990–2019: an analysis of data from the Global Burden of Disease Study 2019

Burkart, Katrin | 2022

Background Experimental and epidemiological studies indicate an association between exposure to particulate matter (PM) air pollution and increased risk of type 2 diabetes. In view of the high and increasing prevalence of diabetes, we aimed to quantify the burden of type 2 diabetes attributable to PM2·5 originating from ambient and household air pollution. Methods We systematically compiled all relevant cohort and case-control studies assessing the effect of exposure to household and ambient fine particulate matter (PM2·5) air pollution on type 2 diabetes incidence and mortality. We derived an exposure–response curve from the extracted relative risk estimates using the MR-BRT (meta-regression— Bayesian, regularised, trimmed) tool. The estimated curve was linked to ambient and household PM2·5 exposures from the Global Burden of Diseases, Injuries, and Risk Factors Study 2019, and estimates of the attributable burden (population attributable fractions and rates per 100000 population of deaths and disability-adjusted life-years) for 204 countries from 1990 to 2019 were calculated. We also assessed the role of changes in exposure, population size, age, and type 2 diabetes incidence in the observed trend in PM2·5-attributable type 2 diabetes burden. All estimates are presented with 95% uncertainty intervals. Findings In 2019, approximately a fifth of the global burden of type 2 diabetes was attributable to PM2·5 exposure, with an estimated 3·78 (95% uncertainty interval 2·68–4·83) deaths per 100 000 population and 167 (117–223) disabilityadjusted life-years (DALYs) per 100000 population. Approximately 13·4% (9·49–17·5) of deaths and 13·6% (9·73–17·9) of DALYs due to type 2 diabetes were contributed by ambient PM2·5, and 6·50% (4·22–9·53) of deaths and 5·92% (3·81–8·64) of DALYs by household air pollution. High burdens, in terms of numbers as well as rates, were estimated in Asia, sub-Saharan Africa, and South America. Since 1990, the attributable burden has increased by 50%, driven largely by population growth and ageing. Globally, the impact of reductions in household air pollution was largely offset by increased ambient PM2·5. Interpretation Air pollution is a major risk factor for diabetes. We estimated that about a fifth of the global burden of type 2 diabetes is attributable PM2·5 pollution. Air pollution mitigation therefore might have an essential role in reducing the global disease burden resulting from type 2 diabetes

Musculoskeletal symptomatology in postharvest workers of a flower farm in Cundinamarca

Orozco Vásquez, Margarita María | 2022

Objetivos: Los síntomas musculoesquelético son una de las principales causas de perdida de la capacidad laboral y ausentismo en el mundo del trabajo. Los trabajadores de cultivo de flores están predispuestos a sufrirlas debido a la naturaleza de su trabajo. El Objetivo fue identificar la sintomatología musculoesquelética en los diferentes segmentos corporales. Material y Métodos: Estudio descriptivo con enfoque cuantitativo, la población fueron 135 trabajadores del área de postcosecha de un cultivo de flores ubicado en un municipio aledaño a la ciudad de Bogotá; se aplicaron 2 instrumentos, una encuesta de caracterización sociodemográfica y el cuestionario Nórdico Estandarizado. Resultados: Los segmentos corporales con presencia de síntomas fueron, la muñeca derecha 34%, espalda alta 32%, baja 27%, pies y tobillos 26%. El 99% de los rabajadores, atribuye su sintomatología músculo esquelética a la actividad laboral

The economic well-being of nations is associated with positive daily situational experiences

Gardiner, Gwendolyn | 2023

People in economically advantaged nations tend to evaluate their life as more positive overall and report greater well-being than people in less advantaged nations. But how does positivity manifest in the daily life experiences of individuals around the world? The present study asked 15,244 college students from 62 nations, in 42 languages, to describe a situation they experienced the previous day using the Riverside Situational Q-sort (RSQ). Using expert ratings, the overall positivity of each situation was calculated for both nations and individuals. The positivity of the average situation in each nation was strongly related to the economic development of the nation as measured by the Human Development Index (HDI). For individuals’ daily experiences, the economic status of their nation also predicted the positivity of their experience, even more than their family socioeconomic status. Further analyses revealed the specific characteristics of the average situations for higher HDI nations that make their experiences more positive. Higher HDI was associated with situational experiences involving humor, socializing with others, and the potential to express emotions and fantasies. Lower HDI was associated with an increase in the presence of threats, blame, and hostility, as well as situational experiences consisting of family, religion, and money. Despite the increase in a few negative situational characteristics in lower HDI countries, the overall average experience still ranged from neutral to slightly positive, rather than negative, suggesting that greater HDI may not necessarily increase positive experiences but rather decrease negative experiences. The results illustrate how national economic status influences the lives of individuals even within a single instance of daily life, with large and powerful consequences when accumulated across individuals within each nation.

Adjuvants approved for human use: What do we know and what do we need to know for designing good adjuvants?

Reyes, César | 2023

Adjuvants represent one of the most significant biotechnological solutions regarding vaccine development, thereby broadening the amount of candidates which can now be used and tested in vaccine formulations targeting various pathogens, as antigens which were previously discarded due to their low or null immunogenicity can now be included. Adjuvant development research has grown side-by-side with an increasing body of knowledge regarding immune systems and their recognition of foreign microorganisms. Alum-derived adjuvants were used in human vaccines for many years, even though complete understanding of their vaccination-related mechanism of action was lacking. The amount of adjuvants approved for human use has increased recently in line with attempts to interact with and stimulate the immune system. This review is aimed at summarising what is known about adjuvants, focusing on those approved for use in humans, their mechanism of action and why they are so necessary for vaccine candidate formulations; it also discusses what the future may hold in this growing research field

Unusual presentation of melanoma during the puerperium

Lamus, Sergio | 2023

El objetivo del artículo es describir las manifestaciones clínicas y el enfoque diagnóstico realizado en una paciente que presentó un melanoma durante el puerperio.

Neotropical ornithology: Reckoning with historical assumptions, removing systemic barriers, and reimagining the future

Soares, Letícia | 2023-02

A major barrier to advancing ornithology is the systemic exclusion of professionals from the Global South. A recent special feature, Advances in Neotropical Ornithology, and a shortfalls analysis therein, unintentionally followed a long-standing pattern of highlighting individuals, knowledge, and views from the Global North, while largely omitting the perspectives of people based within the Neotropics. Here, we review current strengths and opportunities in the practice of Neotropical ornithology. Further, we discuss problems with assessing the state of Neotropical ornithology through a northern lens, including discovery narratives, incomplete (and biased) understanding of history and advances, and the promotion of agendas that, while currently popular in the north, may not fit the needs and realities of Neotropical research. We argue that future advances in Neotropical ornithology will critically depend on identifying and addressing the systemic barriers that hold back ornithologists who live and work in the Neotropics: unreliable and limited funding, exclusion from international research leadership, restricted dissemination of knowledge (e.g., through language hegemony and citation bias), and logistical barriers. Moving forward, we must examine and acknowledge the colonial roots of our discipline, and explicitly promote anti-colonial agendas for research, training, and conservation. We invite our colleagues within and beyond the Neotropics to join us in creating new models of governance that establish research priorities with vigorous participation of ornithologists and communities within the Neotropical region. To include a diversity of perspectives, we must systemically address discrimination and bias rooted in the socioeconomic class system, anti-Blackness, anti-Brownness, anti-Indigeneity, misogyny, homophobia, tokenism, and ableism. Instead of seeking individual excellence and rewarding top-down leadership, institutions in the North and South can promote collective leadership. In adopting these approaches, we, ornithologists, will join a community of researchers across academia building new paradigms that can reconcile our relationships and transform science. Spanish and Portuguese translations are available in the Supplementary Material.

Utilización de subproducto de naranja en la alimentación de conejos en engorde

Díaz Vargas, Mayra | 2022-05-03

El objetivo del presente estudio fue evaluar la utilización de subproductos de naranja deshidratada en dietas para conejos en etapa de engorde. La cáscara fue analizada mediante un bromatológico, dando como resultado un aporte de 7.4% de PB, 14.87% de FC, 3.8% de EE, 5.1 de MM, 4308 kcal/kg de EB y 385.76 mg de polifenoles. En el primer ensayo se realizó una prueba de digestibilidad utilizando 24 conejos adultos distribuidos en 4 tratamientos de porcentaje de sustitución de la pulpa cítrica (0, 10, 20 y 30) por el alimento balanceado a razón de 6 repeticiones. En el segundo experimento de desempeño y calidad de carne se utilizaron los mismos tratamientos y se usaron 2 animales por repetición, totalizando 48 animales recién destetos. Los coeficientes de digestibilidad para FDA y MM mostraron resultados lineales decrecientes, por contraparte, ELN y MS presentan un comportamiento lineal creciente indicando una mejor digestibilidad a medida que aumentaba el porcentaje de sustitución. Los parámetros de desempeño zootécnico tuvieron diferencia significativa (p<0.05) con el 20% de sustitución para ganancia de peso y conversión alimenticia, sin afectar en rendimiento en canal y calidad de carne. Se concluye que el subproducto de naranja deshidratado puede sustituir hasta un 30% el concentrado comercial, optimizando el desempeño de los animales sin alterar aspectos de calidad cárnica.

Semillero de Salud Mental 2022-2

Higuera Dagovett., Elkin Crisostomo | 2023-02-07

Describe los proyectos de investigación relacionados con la temática de Salud Mental, los tipos de actividad,las personas que intervienen y el cronograma para su ejecución.

Proteases na alimentação de frangos de corte

Díaz Vargas, Mayra | 2022

A inclusão de aditivos na alimentação de frangos de corte tem sido uma estratégia para reduzir os custos de produção, sendo o ponto central das pesquisas na avicultura, uma vez que a alimentação equivale a 70% do custo total de produção. O objetivo desta revisão é apresentar uma atualização sobre os benefícios do uso de proteases adicionadas à dieta de frangos de corte e como elas são oportunidades para melhorar variáveis produtivas como desempenho das aves, digestibilidade de nutrientes da ração e parâmetros hismorfométricos intestinais. Além disso, foi destacado que sua inclusão pode aumentar a energia metabolizável aparente e diminuição da proteína que chega ao cólon, que podem gerar síndromes inflamatórias intestinais e levar à diarreia, além de servir de substrato para o crescimento de bactérias patogênicas. Alguns estudos de viabilidade econômica mostraram que, quando manejadas dietas hipoproteicas com adição de protease, se pode ter melhor rentabilidade do que dietas comerciais totalmente balanceadas. Por isso, novas pesquisas devem ser realizadas.

Atención Primaria en Salud en una región de la Amazonía colombiana: una aproximación al cotidiano

De Mattos Penna, Cláudia Maria | 2022

En 2016 comenzó en Colombia la implantación de un nuevo modelo de salud con foco en la atención primaria, siendo Guainía, en la Amazonía colombiana, la primera región en iniciar el test piloto. El objetivo de este estudio fue comprender el cotidiano de implementación de la atención primaria, en el marco del Modelo Integral de Atención en Salud, desde la perspectiva de indígenas y profesionales de la salud en Guainía, Colombia. Se trata de un estudio de caso único, con abordaje cualitativo, fundamentado en la sociología comprensiva del cotidiano. Los datos, recolectados mediante observación directa y entrevistas semiestructuradas con 26 profesionales de salud y 22 usuarios indígenas, fueron sometidos a análisis de contenido temático. Emergieron cinco categorías: ‘vivir en el puesto’, ‘resolver solo’, ‘el desafío de la cobertura territorial’, ‘comisiones de salud: solventando vacíos’ y ‘apoyo de líderes locales’. A pesar de la propuesta reestructurante traída por el nuevo modelo, se evidenció en el cotidiano la persistencia de un enfoque asistencialista y basado en la lógica curativista en la prestación de los servicios. Aunque los atributos de la atención primaria se ven comprometidos, se identificaron acciones cotidianas que pueden favorecer la integralidad en la atención y aportar a una transición exitosa.

Current and Future Climate Extremes Over Latin America and Caribbean: Assessing Earth System Models from High Resolution Model Intercomparison Project (HighResMIP)

Avila Diaz, Alvaro Javier | 2023

Extreme temperature and precipitation events are the primary triggers of hazards, such as heat waves, droughts, floods, and landslides, with localized impacts. In this sense, the finer grids of Earth System models (ESMs) could play an essential role in better estimating extreme climate events. The performance of High Resolution Model Intercomparison Project (HighResMIP) models is evaluated using the Expert Team on Climate Change Detection and Indices (ETCCDI) over the 1981–2014 period and future changes (2021–2050) under Shared Socioeconomic Pathway SSP5–8.5, over ten regions in Latin America and the Caribbean. The impact of increasing the horizontal resolution in estimating extreme climate variability on a regional scale is first compared against reference gridded datasets, including reanalysis, satellite, and merging products. We used three different groups based on the resolution of the model’s grid (sg): (i) low (0.8° ≤ sg ≤ 1.87°), (ii) intermediate (0.5° ≤ sg ≤ 0.7°), and (iii) high (0.23° ≥ sg ≤ 0.35°). Our analysis indicates that there was no clear evidence to support the posit that increasing horizontal resolution improves model performance. The ECMWF-IFS family of models appears to be a plausible choice to represent climate extremes, followed by the ensemble mean of HighResMIP in their intermediate resolution. For future climate, the projections indicate a consensus of temperature and precipitation climate extremes increase across most of the ten regions. Despite the uncertainties presented in this study, climate models have been and will continue to be an important tool for assessing risk in the face of extreme events

A New Flavanone from Chromolaena tacotana (Klatt) R. M. King and H. Rob, Promotes Apoptosis in Human Breast Cancer Cells by Downregulating Antiapoptotic Proteins

Mendez, Gina | 2023

Chromolaena tacotana is a source of flavonoids with antiproliferative properties in human breast cancer cells, the most common neoplasm diagnosed in patients worldwide. Until now, the mechanisms of cell death related to the antiproliferative activity of its flavonoids have not been elucidated. In this study, a novel flavanone (3′,4′-dihydroxy-5,7-dimethoxy-flavanone) was isolated from the plant leaves and identified by nuclear magnetic resonance (NMR) and mass spectrometry (MS). This molecule selectively inhibited cell proliferation of triple-negative human breast cancer cell lines MDA-MB-231 and MCF-7 whit IC50 values of 25.3 μg/mL and 20.8 μg/mL, respectively, determined by MTT assays with a selectivity index greater than 3. Early and late pro-apoptotic characteristics were observed by annexin-V/7-AAD detection, accompanied by a high percentage of the Bcl-2 anti-apoptotic protein inactivated and the activation of effector Caspase-3 and/or 7 in breast cancer cells. It was verified the decreasing of XIAP more than Bcl-2 anti-apoptotic proteins expression, as well as the XIAP/Caspase-7 and Bcl-2/Bax complexes dissociation after flavanone treatment. Docking and molecular modeling analysis between the flavanone and the antiapoptotic protein XIAP suggests that the natural compound inhibits XIAP by binding to the BIR3 domain of XIAP. In this case, we demonstrate that the new flavanone isolated from leaves of Chomolaena tacotana has a promising and selective anti-breast cancer potential that includes the induction of intrinsic apoptosis by downregulation of the anti-apoptotic proteins XIAP and Bcl-2. New studies should deepen these findings to demonstrate its potential as an anticancer agent.

In vitro production of buffalo embryos in Colombia – results of the addition of growth factors and antioxidants to defined culture medium

Chavez Rodriguez, Aldemar | 2023

To increase the success rate of the in vitro production (IVP) system of embryos in buffalo, it is necessary to improve parameters. This field requires more research since its results are low compared to cattle. In this study carried out in Colombia, a modification of the methodology to produce buffalo IVP embryos is described, and 24 non-lactating females, aged 4 to 11 years old were included. Follicular wave was synchronised by ablation of the follicles within the ovary, seven days later all follicles were aspirated to obtain oocytes for maturation, fertilisation and embryo production. For all culture media used, animal protein was avoided. Culture media were supplemented with growth factors and other molecules associated with embryonic development. Special care was taken in adding supplements to protect the zygotes against the harmful effect of oxygen free radicals in the culture medium. Two aspiration series were performed 15 days apart. The average number of oocytes obtained by aspiration was 11.33, the number of blastocysts was 3.05, and the obtained blastocyst production rate (36.2%) was higher than literature reports for this species; we hypothesise that this increase is associated with the supplements added. It was possible to observe a female that produced 50 oocytes. Subsequent research is needed to evaluate the effect of the medium on embryo quality and pregnancy rates. A cost analysis of the new proposed medium is required, since all supplements must be imported and handled with a cold chain of up to -80oC, making it more expensive and restricting widespread use. Finally, it is shown that with three embryos per aspiration, at least one pregnancy can be successful after the aspiration, which is one of the objectives of the IVP system

Acute appendicitis during the COVID-19 pandemic: Experience in a high-level complex center in Boyacá, Colombia

Támara-López, José Antonio | 2023

Introduction. The COVID-19 pandemic varied the way health systems were attended, thus affecting pathologies not related to respiratory infections, such as acute appendicitis. Fear of SARS-CoV-2 infection and mobility restrictive measures may have implied a longer time from the onset of symptoms to consultation of the emergency department, leading to intraoperative and postoperative complications. Methods. Retrospective cross-sectional descriptive observational study, identifying all patients diagnosed with acute appendicitis and taken for appendectomy, divided into two groups, considered pre-pandemic, from September 1, 2018 to March 15, 2020, and pandemic, from March 16, 2020 to September 30, 2021. Results. One-thousand patients were identified, 501 patients were distributed in the pre-pandemic group and 499 in the pandemic group. The average consultation time from the time of onset of symptoms to consultation was 43 hours in the pre-pandemic group and almost 45 hours in the pandemic. Discussion. Despite the restrictions due to the disease caused by the new coronavirus and the fear that may existed due to contagion, in our center there was no evidence of a change in the management and presentation of patients diagnosed with acute appendicitis.

Characterization of variables associated with sports performance: interdisciplinarity in women's soccer in Colombia

Becerra Patiño, Boryi Alexander | 2023

Characterizing the variables associated with sports performance in women's soccer is necessary to favor the sports preparation of the player. This study aimed to evaluate the association between performance characteristics (morphofunctional) and characteristics (psychosocial and nutritional) in female soccer players in Bogota. The study included 81 players grouped by position, based on the analysis of morphological (somatotype), functional (endurance, speed, and strength), psychosocial (socioeconomic status, economic situation, educational level, subsidized health regime, family members), and nutritional (dietary habits, food, quantity and type of food and intolerances) variables. A total of 241 variables were analyzed, grouped into 21 groups of variables, of which eight groups were analyzed in depth and showed statistically significant differences. The study had a quantitative approach, correlational study type, and non-experimental crosssectional design with Bernoulli sampling. The statistical treatment was performed using the statistical program ® version 4.1.0 based on the principal component analysis method, multiple factor analysis, and RV coefficient. It can be evidenced that the profile induced by the position variable correlates with the profile induced by the group of RSA variables. The profile induced by the lower body strength variables correlates with the profile induced by the social variables. The lower body strength variables and the social and family characteristics reveal that players living above 2550 meters of altitude are characterized by having high values in variables such as net strength at 100, 150, and 200 m/s, left-right leg, and vertical peak strength. These are in the subsidized regime and are characterized by living in small families. In contrast, players living at an altitude of 2600 meters were characterized by reaching high levels in variables such as peak power (W/kg), jump height (cm), reactive force index (m/s), eccentric deceleration (N/s/kg), maximum peak velocity (m/s), average concentric force and average eccentric force, characterized by living in more prominent families. Thus, it can be determined that the context of female athletes significantly influences the muscle strength manifestation profile. Finally, the importance of interdisciplinarity in women's soccer is highlighted, seeking to understand that sports performance depends on the interaction of variables. Thus, interdisciplinary research opens a scenario of possibilities where the different variables that influence the sports performance of female soccer players and athletes can be understood under the interactions that occur in the competitive act. © 2023, Editura Universitatii din Pitesti. All rights reserved.

Improving sustainability teaching by grouping and interrelating pedagogical approaches and sustainability competences: Evidence from 15 Worldwide Higher Education Institutions

Lozano, Rodrigo | 2023

Education Institutions (HEIs). This paper's aim is to provide deeper insights into the system of pedagogical approaches and sustainability competences, as well as how these interrelate. A survey was developed to investigate sustainability teaching in 15 HEIs. The survey was sent to educators of each HEI from which 668 responses were obtained. The responses were analysed in a five-step process: (1) descriptive statistics; (2) Pearson correlations; (3) principal component analyses (PCAs) to detect groups; (4) Pearson correlations between the groups; and (5) regressions. The first step provided the base to carry out the PCAs, from which three groups for the pedagogical approaches (Universal, Social, and Environmental) and three for the sustainability competences (Extrospective-social, Introspective-personal, and Cogitative-processual) were obtained. The correlations between the groups showed that: (1) the competences are closely interrelated; (2) the pedagogical approaches are somehow interrelated; and (3) the pedagogical approaches are somehow interrelated to the competences. The regressions showed that the Universal and Social groups would be most suitable to develop all the competences' groups. The Environmental group develops only the cogitative-processual competences' group. The results served as bases to propose the Sustainability Teaching System (STS), which provides deeper insights into the system of pedagogical approaches and sustainability competences by grouping them, as well as showing directionality and strength. To improve sustainability teaching, it is necessary to understand the pedagogical approaches' groups and how they can develop the competences' groups.

Burden of infectious disease studies in Europe and the United Kingdom: a review of methodological design choices

Charalampous, Periklis | 2023

This systematic literature review aimed to provide an overview of the characteristics and methods used in studies applying the Disability-Adjusted Life Years (DALY) concept for infectious diseases within European Union (EU)/European Economic Area (EEA)/European Free Trade Association (EFTA) countries and the United Kingdom. Electronic databases and grey literature were searched for articles reporting the assessment of DALY and its components. We considered studies in which researchers performed DALY calculations using primary epidemiological data input sources. We screened 3,053 studies of which 2,948 were excluded and 105 studies met our inclusion criteria. Of these studies, 22 were multi-country and 83 were single-country studies, of which 46 were from the Netherlands. Food- and water-borne diseases were the most frequently studied infectious diseases. Between 2015 and 2022, the number of burden of infectious disease studies was 1.6 times higher compared to that published between 2000 and 2014. Almost all studies (97%) estimated DALYs based on the incidence- and pathogen-based approach and without social weighting functions; however, there was less methodological consensus with regards to the disability weights and life tables that were applied. The number of burden of infectious disease studies undertaken across Europe has increased over time. Development and use of guidelines will promote performing burden of infectious disease studies and facilitate comparability of the results.

Cryostorage of white cachama (Piaractus orinoquensis) sperm: Effects on cellular, biochemical and ultrastructural parameters

Medina Robles, Victor Mauricio | 2023

To date, little attention has been paid to identifying the effects of long-term cryopreservation on sperm quality for Piaractus orinoquensis. The object of this study was therefore to evaluate the effect of long-term cryopreservation (24 h, 1, 6 and 12 months) on sperm motility, viability, DNA integrity, ATP content, total antioxidant capacity (TAC), morphology and sperm ultrastructure in this species. Milt samples from six males were cryopreserved in a medium containing final concentrations of 7.5% Me2SO, 4.1% glucose and 9.0% egg yolk. The samples were frozen in liquid nitrogen (LN) vapor and stored in LN for periods of 24 h and 1, 6 and 12 months. After thawing, both the motility rate and the viability decreased significantly compared with fresh sperm; however, these parameters did not differ among the four cryopreservation times. The DNA integrity and ATP content decreased significantly after 6 months of cryopreservation. There were no significant differences in TAC values between fresh and cryopreserved sperm. The total sperm abnormalities in cryopreserved samples were about 5-fold higher than in fresh sperm; short tail was the most common defect occurring after cryostorage. The ultrastructural analysis reveals that P. orinoquensis spermatozoa consist of an ovoid head without acrosome, a cylindrical mid-piece, and a single flagellum. The nuclear fossa is located at the base of the nucleus and contains the centriolar complex. There are 1–2 ring-shaped mitochondria located in the mid-piece. The flagellum shows a 9 + 2 organization of microtubules in the axoneme. Post-thaw spermatozoa presented damage such as swelling and rupture of the plasma membrane, mitochondrial damage, loss of the electron-dense chromatin of the nucleus, and degeneration in the middle region

Existencia de Puntos fijos comunes a partir de un algoritmo con perturbaciones en espacios de curvatura no positiva para aplicaciones contractivas generalizadas

Calderón Sánchez, Kenyi Javier | 2022-09-19

En este proyecto se planteó un algoritmo de punto fijo perturbado de tres pasos para lograr la convergencia en un operador de tipo contractivo. Para esto se demostraron algunos de teoremas de convergencia y estabilidad del algoritmo propuesto. Posterior a ello se establecen algunas aplicaciones en ecuaciones integrales donde se demuestra la importancia del algoritmo para la solución de dichas que ecuaciones las cuales son muy comunes en diversas áreas de las ciencias. Los resultados obtenidos fueron presentados en el artículo titulado “Some stability and strong convergence results for the algorithm with perturbations for T-Ciric quasi contraction in CAT(0) spaces”. Finalmente, el artículo generaliza varios resultados que se encuentran actualmente en la literatura.

Evaluación de índices de selección genética para la optimización de procesos de cría en programas de mejoramiento genético de razas bovinas criollas en Colombia

Amaya Martínez, Adonai Alejandro | 2022-09-30

Este proyecto de investigación tuvo como objetivo evaluar índices de selección genética en dos poblaciones bovinas de razas criollas colombianas, la raza Blanco Orejinegro y la raza Romosinuano. Una evaluación genética del peso a los 24 meses de edad, la edad al primer parto y el intervalo entre partos fue usada para la estimación de los índices. Posteriormente, cada característica fue ponderada de tres maneras diferentes para la construcción de los índices: el primer índice derivado a partir de un modelo bioeconómico, el cual consideró las condiciones productivas y económicas de los sistemas ganaderos colombianos que usan estos recursos genéticos en Colombia, el segundo índice consideró la varianza fenotípica de las características a seleccionar y el tercer índice consideró, de manera simultánea la estructura de varianzas y covarianzas entre las características a través de un análisis de componentes principales. Una vez construidos los índices se estimó el mérito genético total de cada animal en cada índice y se calcularon las correlaciones entre el ordenamiento de los animales. Finalmente, simulaciones de apareamientos fueron realizadas con el objetivo de predecir el progreso genético bajo diferentes escenarios de intensidades de selección genética y usando cada índice. Una vez estimado el progreso genético, se calcularon las contribuciones económicas de cada una de las características evaluadas a la rentabilidad del sistema. En las dos razas, la característica con mayor ponderación económica fue el intervalo entre partos (-1,3 USD), seguido de la edad al primer parto (-0,31) y el peso a los 24 meses de edad (0,16 USD). Para el análisis de componentes principales, la característica con mayor peso fue el peso a los 24 meses, con un valor de 0,56. El peso a los 24 meses también fue el de mayor ponderación (0,034) al usar la varianza fenotípica como ponderador. La correlación de los índices fue 0,98 entre la ponderación por componentes principales y la varianza fenotípica, pero fue baja (inferior a 0,55) cuando estos fueron comparados con el índice de selección económico. Respecto al progreso genético esperado, el peso a los 24 meses de edad reportó ganancias entre 13 y 14 kg en una generación, con una intensidad de selección del 70 y 10% para hembras y machos, respectivamente. Para las características reproductivas, el intervalo entre partos tuvo un mayor progreso al usar el índice económico, con un valor de 12 días aproximadamente, lo cual generó una mayor ganancia económica que los 14 kilos conseguidos en el peso a los 24 meses en los otros dos índices. Estos resultados indican que la metodología más eficiente para aumentar el rendimiento biológico y económico en un sistema de producción es la ponderación que considera las condiciones actuales a nivel de producción y económicas de los sistemas en los cuales se desempeñan las razas de interés. Estos resultados permiten facilitar la toma de decisiones al identificar los animales con mayor potencial genético que maximizan la utilidad económica mediante procesos de selección genética.