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Medición de la dosis equivalente en órganos torácicos debido a estudios tomográficos mediante el diseño y construcción 3D de un fantoma de tórax
Get PDFUna de las ramas de la física se orienta, en conjunto con la medicina, al desarrollo de modelos aproximados que explican el funcionamiento del cuerpo humano bajo las leyes físicas. El objetivo de la física médica es proporcionar diagnósticos y apoyar el tratamiento de enfermedades. Gracias a su considerable avance tecnológico, esta área tiene un gran impacto en la comunidad científica y médica, y es fuente de investigación para disciplinas como la ingeniería, la medicina y la biología, entre otras.
En este trabajo se construye un fantoma antropomórfico torácico mediante un diseño computarizado que incluye corazón, pulmones, tráquea y costillas. Los modelos se imprimen con una impresora 3D, teniendo en cuenta el porcentaje de relleno necesario para aproximar la densidad de los órganos en unidades Hounsfield (HU). Para lograr una representación precisa, se emplea un material específico en el corazón que se asemeja a su valor HU, mientras que las costillas se modelan con el apoyo de la empresa The Cave: Creature Workshop, con el fin de simular correctamente su densidad en HU. Es importante que los órganos mantengan una estructura coherente con la anatomía humana.
Posteriormente, se realizan perforaciones en cada órgano para insertar los dosímetros encargados de medir la dosis equivalente personal en cada uno de ellos cuando el fantoma se introduce en el tomógrafo del Centro de Cuidados Cardioneurovasculares Pabón SAS. Tras la lectura de los dosímetros, se aplica la conversión matemática correspondiente para obtener la dosis absorbida.
Dado que este tipo de estudio no se había realizado previamente a nivel regional, su desarrollo tiene un impacto significativo en el ámbito científico, al ofrecer una perspectiva novedosa en el estudio de la dosimetría.
En la sustentación de grado los pares evaluadores fueron Jaime Betancourt y Fredy Santacru
Formación de grupos en escenarios de trabajo colaborativo: un enfoque desde la personalidad y los algoritmos genéticos
Get PDFFormulación de Hamilton-Jacobi para la ecuación de Proca
Get PDFEn este trabajo se aplica la formulación de Hamilton-Jacobi al campo de Proca, tanto para campos reales como complejos. La ecuación de Proca, una extensión de las ecuaciones de Maxwell, describe el comportamiento de partículas bosónicas masivas. Este estudio busca proporcionar una descripción alternativa a la teoría canónica tradicional mediante el uso del formalismo de Hamilton-Jacobi. Se han derivado las condiciones de integrabilidad, las ecuaciones características y se han construido corchetes generalizados para ambos tipos de campo. Además, se exploran las implicaciones de introducir una simetría de gauge local, lo cual ofrece una comprensión más profunda de la dinámica de los campos bosónicos. Los resultados confirman que la formulación de Hamilton-Jacobi es una herramienta efectiva para analizar y comprender la dinámica de los campos de Proca, validando su equivalencia con el enfoque canónico y ampliando el conocimiento en este campo.
En la sustentación de tesis los pares evaluadores fueron Juan Carlos Salazar y Eduardo Roja
Standardized rearing process of the black soldier fly (Hermetia illucens) under marginal conditions for bioprospecting purposes
Get PDFThere is growing interest in large-scale breeding of black soldier fly (BSF) larvae due to their ability to consume a wide variety of organic materials. This study aimed to standardize the key developmental phases of Hermetia illucens within a rearing unit under marginal conditions (2160 meters above sea level; Temperature 14 °C average annual precipitation of 1800 mm) in an Andean Temperate Forest ecosystem. The primary objective was to optimize the production of 5-day-old larvae. A subdivided plot design was employed, incorporating two cage types, three attractants types, two glasses and three egg-laying sites, with three replicates for each combination, resulting in a total of 108 experimental units. The following factors were compared: cage type (Zurbrügg type cage and a cage proposed by the University of Caldas), attractant (organic waste, fermented waste, and a mixture containing 100 grams of dead black soldier fly adults), drinkers (cotton and sponge) and egg-laying sites (three different dimensions (A: 45 cm x 12 cm x 7 cm, B: 24 cm x 7 cm x 3 cm, and C: 12 cm x 1.2 cm x 0.5 cm)The combination of the University of Caldas cage, sponge drinkers, and the type C attractant yielded the most promising results in terms of egg weight and projected larval population size under the specific marginal conditions of the study area. The findings of this study will help to promote strategies to transform organic waste using BSF larvae in marginal conditions
Spatio-temporal distribution of Dengue, Zika and Chikungunya in Cali, Colombia: 2014-2016
Get PDFIntroduction: Emerging and re-emerging arboviral infections have become a public health challenge in the Americas due to their epidemic potential. Objective: To determine the spatio-temporal distribution of the dengue, Zika, and chikungunya viruses during an epidemic period in Cali, Colombia. Materials and methods: Multi-method descriptive ecological and exploratory study of confirmed and suspected cases reported to the epidemiological surveillance system between 2014 and 2016. Results: 40,168 cases were analyzed, and it was found that dengue was the most frequent arboviral infection (59.2 %). The most affected individuals were women (65 %) and those with a mean age of 34.5 years. Although arboviral infections spread out throughout the city, the three diseases were concentrated in significant groups located at the center-east and northeast areas of Cali (p<0.01; z=-203.7). Conclusions: This study identified critical zones for the three arboviral infections, which are located in areas with low socioeconomic status. Likewise, the results suggest that in addition to eco-epidemiological and bio-psychosocial factors, temperature, precipitation, and the aedic index may play an important role in the spatio-temporal behavior of these diseases. A multidisciplinary and collaborative approach is necessary, which must involve communities and authorities to implement effective control strategies, especially during epidemic periods
Monitoring of food handlers and their influence on the preparation of ready-to-eat foods
Get PDFIntroduction: Transmission of foodborne pathogensis related to inadequate sanitary conditions, which are derived from either the food preparation process or the person who prepares it. Food handlers are essentialto preserve food innocuousness and protect consumer’s health. Objective: To evaluate demographic characteristics, hygiene practices, knowledge, work conditions and the presenceof pathogenic microorganisms infood handlers at public school restaurants inAntioquia, Colombia. Materials and methods: The study evaluated 104 food handlers in a municipality in Antioquia. Demographic data and stool samples were collected to identify intestinal parasites, Salmonella spp., andStaphylococcus aureus. Results:The presence of intestinal parasites (e.g.Entamoeba Complex and Trichuris trichiura)was identified in 61% of female participants. Staphylococcus aureus was isolated from 49% of food handlers.Conclusion: Infection of food handlerwas confirmed, making them potential sources of food contamination. They are committed to their work and have the knowledge to preserve basic hygieneconditions.It is highlighted their importance and influenceinadequate hygienic practices to minimize the risks of transmission, as wellas the need for medical treatment and regular checkups offood handlers to counteract the risk to consumers
Antimicrobial and molecular resistance profiles of bacterial isolates from poultry production environment
Get PDFPoultry farming is a relevant industry in Brazil, providing essential animal protein. However, such commercial activity faces significant challenges from bacterial-based diseases, which can impact both animal health and quality product. In this context, this study aimed to identify bacterial strains and evaluate their antimicrobial resistance profiles in poultry farms in southern Tocantins, Brazil. Samples were collected from different stages of poultry production, and the antimicrobial susceptibilities were assessed through antibiogram tests, where bacterial isolates were exposed to 17 antibiotics commonly used in bacterial infection treatment. Bacterial isolates were identified by 16S rRNA gene sequencing, and phylogenetic analysis was used to group them based on genetic similarities. Five isolates were identified: Glutamicibacter creatinolyticus (IGA1), Enterococcus gallinarum (IGA2), Enterobacter mori (IGA3), Lysinibacillus fusiformis (IGA4), and Enterococcus faecalis (IGA5). Antibiotic susceptibility tests revealed significant variations in resistance profiles, with some isolates exhibiting multidrug-resistant (MDR) phenotypes. IGA1 was classified as multidrug-resistant, showing resistance to imipenem, meropenem, ceftazidime, trimethoprim, and doxycycline. IGA2 exhibited resistance to β-lactam antibiotics, including ceftazidime, cefepime, doxycycline, imipenem, meropenem, piperacillin-tazobactam, and tetracycline. IGA3 was resistant to aztreonam and trimethoprim, while IGA4 showed resistance to ceftazidime and cefepime but sensitivity to ciprofloxacin and linezolid. IGA5 did not show resistance to any of the tested antimicrobials. Collectively, our findings highlight bacterial diversity and antibiotic resistance in poultry fams, reinforcing the need for continuous monitoring and effective antimicrobial control strategies to promote animal health, ensure food safety, and prevent the transmission of multidrug-resistant bacteria to humans
La guitarra eléctrica y el rock - metal como propuesta final de un proceso académico - clásico
Get PDFSe presenta como proyecto de grado, composiciones propias y arreglos a partir de géneros alternativos siendo el rock, el metal y sus subgéneros la elección para crear e interpretar en la guitarra eléctrica, instrumento de estudio principal del autor escogido para la modalidad recital creativo; el proyecto, además de aportar en cuanto a compresión de la historia, relevancia y procesos actuales del instrumento en los géneros alternativos, es muestra que da a conocer cómo, para el autor e interesados, la guitarra eléctrica en aquel tipo de música llega a ser versátil para aprender recursos técnicos únicos que requieren destreza y habilidad desbordando más posibilidades interpretativas y de composición llegando a un estilo propio dentro de aspectos musicales técnicos - teóricos - experimentales y sonoros; con ello se complementa el abordaje de musicalidad y el mundo sonoro interno, aspecto etéreo de importancia intangible, donde el conocimiento adquirido y recorrido en el instrumento se aprecia en el análisis musical; cada obra, con relación al contexto, esta creada a partir de la liberación emocional, profundidad sentimental y energía donde la expresión corporal individual/colectiva y la actitud con disposición no está exenta, la danza en el rock – metal, su acción - reacción de manera mental - visual también es un punto a reconocer junto a la dificultad que representa para cada interpretación; de esta manera, cada elemento histórico, musical, teórico, técnico, recurso técnico, interpretativo, etéreo - profundo, experimental, sonoro y expresivo (mental, corporal y visual) está respaldado siendo enriquecedor, para el autor en su vida, en el aporte del trabajo escrito y la muestra final, de igual manera dirigido para el futuro interesado o el público en general
Assessment of transitory crops in cocoa (Theobroma cacao L) agroforestry in Páez, Boyacá
Get PDFAgroforestry systems incorporate several productive components per unit area to yield efficiency. However, considering the high degree of complexity inherent to interspecific plant-plant interactions, little is known about most of these systems' real productive potential and efficiency. In this context, it is important to analyze the interactions between the components to identify potential favorable associations. The objective of this research was to evaluate the performance of the transitory crops maize (Zea mays L) and cowpea (Vigna unguiculata L) in a family farming system under three agroforestry arrangements with cocoa in the municipality of Páez, Boyacá, Colombia. A split-plot design was used, where the main plots corresponded to three shade forest species, which were associated with cocoa and the transient crops. The subplots corresponded to three planting systems: CS1 cocoa+maize, CS2 coca+beans, and CS3 cocoa+maize+beans. The effect on agronomic and productive variables of transitory crops (maize and beans) was evaluated, and an economic analysis was carried out. For beans, the effect of the cropping system on yield (t. ha-1) stood out, while for maize, the statistical effect was given by the forest x cropping system interaction in most of the variables evaluated. Considering the interspecific interactions found under the influence of different forests, the use of Colombian mahogany as a companion species in these intercropping systems is suggested. The cost analysis revealed that the maize-bean association is more efficient in the equivalent use of land. Therefore, the data obtained reveal more efficient strategies for sustainable cocoa productivity in Colombia
Control failure of deltamethrin in Colombian populations of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae)
Get PDFRhyzopertha dominica (F.) is a major pest in stored cereals in Colombia, which causes significant losses in production. Chemical control is the main tool used in the country, and despite the common use of insecticides such as deltamethrin, resistance has been observed in some Colombian populations but is a worldwide problem. The objective of this work was to evaluate the efficacy of deltamethrin and the combination of deltamethrin and piperonyl butoxide in Colombian populations of R. dominica. Failure to control and survival tests showed that the recommended doses on product labels were insufficient to protect the grain from this pest. Failure control demonstrated that mortality did not exceed 80 percent in the populations studied. Differences in susceptibility were observed between populations, with El Espinal and Neiva highlighted as less susceptible and Pore as the most sensitive to the action of insecticides. The combination of deltamethrin and piperonyl butoxide reduced insect survival but did not effectively control it (0–20%). These results suggest that R. dominica may be developing resistance to insecticides, as has been found in other countries. This underscores the importance of conducting toxicological studies and the need to investigate molecules with diverse modes of action, contributing to the strengthening of chemical management strategies. To achieve effective control, it is necessary to implement Integrated Pest Management (IPM) with a focus on alternative methods to chemical control