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GENERATION OF LG VECTOR MODES WITH ULTRAHIGH STABILITY BASED ON COMPLEX AMPLITUDE MODULATION IN AN ON-AXIS CONFIGURATION

Gloria Elizabth Rodríguez García (2023, [Tesis de maestría])

"This thesis presents a novel technique for generating vector beams using complex amplitude modulation (CAM) in an on-axis configuration. The holograms used to generate the beams were created using the Mathlab software and displayed on a reflective spatial light modulator (SLM). The main goal of this research was to address both the purity and stability of the beams during generation and propagation, introducing a quantitative approach to assess their stability. As a proof-of-concept, Laguerre-Gaussian vector beams have been generated and characterized using Stokes polarimetry with the proposed experimental set up."

Structured light Laguerre-Gauss vector beams Stokes polarimetry Beam generation Spatial light modulators CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA OPTICA FÍSICA OPTICA FÍSICA

Object manipulation by collaborative autonomous underwater vehicles driven by a model-free second-order sliding mode controller with finite-time convergence

JOSUE GONZALEZ GARCIA (2023, [Artículo])

https://orcid.org/0000-0001-5657-380X

The use of Autonomous Underwater Vehicles (AUV) has expanded in recent years to include them in inspection, maintenance, and repair missions. These missions require the automation of tasks such as autonomous navigation and station-keeping, which are pretty challenging due to the complexity of the vehicle itself and the underwater environment. Traditional control strategies have been used to deal with those problems before, but their performance is limited since they do not consider non-linearities, external disturbances, or model uncertainties. Non-traditional controllers have been explored too, but have shortcomings such as being model-based, parameter-dependant, or so. Additionally, the nature of some objects implies the involvement of multiple vehicles to manipulate them, making the manipulation mission even harder. Collaboration of AUVs is a strong challenge since underwater communications are limited or null. An advanced control strategy dealing with the trajectory tracking and the station-keeping problem would be desirable for simplicity and robustness. If this controller could also help coordinate multiple vehicles without requiring them to communicate with each other, it would make collaborative manipulation tasks reachable. For this purpose, a model-free high-order Sliding Mode Controller (SMC) is presented in this project. Unlike other control approaches, the proposed control strategy achieves finite-time convergence to a practical zero error in a time-base that the user can arbitrarily define. This characteristic will be used to coordinate the navigation of two AUVs to manipulate an object underwater. The performance of the proposed controller was evaluated by numerical simulations and experiments in a semi-Olympic swimming pool and compared with classic and state-of-the-art control strategies regarding trajectory tracking and station-keeping problems. Results have shown that the proposed controller can achieve finite-time convergence of the tracking errors to a practical zero value in the predefined time-base. Results also demonstrated that the convergence time could be arbitrarily selected by the user and achieved by the controller resulting in, as far as the author knows, the first controller with this characteristic for AUVs navigation. The simulations and experiments also showed that the proposed controller outperformed classical and state-of-the-art controllers regarding the Root Mean Square of the tracking errors and energy consumption. Finally, the proposed model-free high-order SMC coordinated two BlueROV2 vehicles in a collaborative manipulation mission without vehicle-to-vehicle communication. Numerical simulation results confirmed that the proposed controller could manage the vehicles to follow a predefined coordinated trajectory to approach, grip, transport, and release an object without communicating with each other.

Doctor of Philosophy In Engineering Science

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LA INSTRUMENTACIÓN INGENIERÍA DE CONTROL INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA NAVAL VEHÍCULOS SUBMARINOS

Diseño de un sistema de ventilación forzada para un invernadero cenital usando CFD

Design of a forced ventilation system for a Zenithal greenhouse using CFD

JORGE FLORES VELAZQUEZ FEDERICO VILLARREAL GUERRERO (2014, [Artículo])

El crecimiento de los cultivos bajo invernadero en México, se ha visto frenado por factores relacionados con el control del clima. El clima producido dentro del invernadero es en gran medida una consecuencia de las condiciones ambientales del lugar donde se localiza el invernadero y del diseño del mismo; así como de la configuración y operación de los sistemas de control como el sistema de ventilación. El análisis del efecto del sistema de ventilación sobre el comportamiento del clima es fundamental para optimizar su manejo. La dinámica de fluidos computacional (CFD) es una técnica numérica que permite analizar el comportamiento del clima del invernadero bajo diferentes escenarios. Esta técnica fue utilizada para modelar el clima de un invernadero cenital de tres capillas. Los resultados indican que la ventana de entrada de aire plana, produce una velocidad media del aire de 0.81±0.69 m s-1, temperatura media de 297.97±1.17 K, temperatura máxima de 303.62 K, un gradiente térmico de 8.67 K, y mostró limitantes en la renovación del aire principalmente en la parte inferior inmediata a la ventana de entrada.

Vegetales Invernaderos Velocidad del viento INGENIERÍA Y TECNOLOGÍA

Gene expression in primary hemocyte culture of the Pacific white shrimp Penaeus vannamei infected with different white spot syndrome virus (WSSV) strains

Delia Patricia Parrilla Taylor REGINA ELIZONDO GONZALEZ Jesús Neftalí Gutiérrez Rivera SILVIA ALEJANDRA GARCIA GASCA NORBERTO VIBANCO PEREZ MA. DE JESUS DURAN AVELAR RICARDO VAZQUEZ JUAREZ (2022, [Artículo])

"Five previously analyzed white spot syndrome virus (WSSV) strains from northwest Mexico,differing in their genome architecture as well as in virulence, were selected (high virulence JP and LG strains;moderate virulence GVE and DIV strains; and low virulence LC10 strain) to evaluate pathogenesis response in vitro. Expression of phagocytosis-activating protein PAP, manganese superoxide dismutase MnSOD and peroxiredoxin PRX, and two genes of immediate-early expression (IE1 and WSSV304) were measured by qPCR in a primary hemocyte cell culture from Penaeus vannamei at 1, 3, 6, 12, and 24 h post-infection (hpi). PAP expression was significantly higher at 1 and 3 hpi, and JP and LC10 strains induced the highest expression. The response of MnSOD was high at 1 hpi, and a significant increase in PRX expression was detected at 3 hpi, probably due to the occurrence of an oxidative burst; expression levels of MnSOD and PRX were significantly higher at 1 and 3 hpi, respectively, induced by the LG strain (high virulence), suggesting an acute response. In general, expression of most immune-related - genes decreased after the initial hours of infection. Expression levels of IE1 and WSSV304 were exceptionally high at 1 hpi in almost all five WSSV analyzed strains,confirming their efficient mechanism for replication and viral fitness. The results of this study do not show an accurate link between the genome size and WSSV virulence of the strains, albeit the strain with the smallest genome showed the highest virulence. All strains induced an early immune response in heterogeneous ways."

Penaeus vannamei, virulence, gene expression, viral fitness, viral pathogenesis, immune response BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) PATOLOGÍA ANIMAL PATOLOGÍA ANIMAL

La ventaja revelada de exportación de la fresa mexicana, su estructura productiva e índices de protección

Karla Anahí Amador García (2008, [Tesis de maestría])

Instituto de Investigaciones Económicas y Empresariales. Maestría en Ciencias en Comercio Exterior

An interest renovated in the natural foods in the world population that puts more attention in its diet exists and in its health. The strawberry is a fruit appreciated by its color, perfume, flavor and benefits for the health since are an anti-rust one and he/she has high quantities of vitamin C, vitamin B, natural sugar, potassium and iron. According to the Association of Warm Supreme TO. C. the consumption of this fruit has associated with a reduction of the cancer prostático and the reduction of the cholesterol LDL (lipoproteína of low density). There is strawberry readiness during the whole year thanks to the development and implementation of new cultivation techniques and of more resistant varieties to almost all the climates. The sector fresero occupies an important place in the economy of Mexico from half-filled of last century for its national and regional great impact as generator of foreign currencies and of employments.

Existe un interés renovado en los alimentos naturales en la población mundial que pone más atención en su dieta y en su salud. La fresa es una fruta apreciada por su color, perfume, sabor y beneficios para la salud ya que es un antioxidante y tiene elevadas cantidades de vitamina C, vitamina B, azúcar natural, potasio y hierro. Según la Asociación de Calidad Suprema A. C. el consumo de esta fruta se ha asociado con una reducción del cáncer prostático y la reducción del colesterol LDL (lipoproteína de baja densidad). Hay disponibilidad de fresa durante todo el año gracias al desarrollo e implementación de nuevas técnicas de cultivo y de variedades más resistentes a casi todos los climas. El sector fresero ocupa un lugar importante en la economía de México desde mediados del siglo pasado por su gran impacto nacional y regional como generador de divisas y de empleos.

CIENCIAS SOCIALES ININEE-M-2008-0006 Exportación Fresa Ventaja comparativa Competitividad VRE

Gestión de los monumentos históricos de propiedad pública en el Centro Histórico de Morelia, 1991-2019

Gauri Ivette García Medina (2020, [Tesis de maestría])

Facultad de Arquitectura. Maestría en Arquitectura, Investigación y Restauración de Sitios y Monumentos

The conservation of the architectural heritage that is under the custody of the Mexican government has not been fully observed as a problem for the administration in this country. Apparently, avoiding the physical deterioration of public monuments, located in federal protection zones, has been a successful task. In contrast to this general perception, the way in which changes in government administration generate ruptures and disengagement in planning regarding ways to protect the architectural heritage was observed from the local level. That is why this research carries out a timely review, evidencing the problem that exists around government management to conserve monuments in the Historic Center of Morelia, from its incorporation as a site in the world heritage list in 1991 until the year of 2019 where a turn of national politics manifests. In order to identify, the level of incidence of the government to carry out actions around the protection of publicly owned historical monuments; The changes of political visions in the different administrative procedures are characterized by evaluating the physical state of the buildings and documenting the way in which the local vision has been gradually transformed in favor of its conservation. By contrasting the political will of several administrations with the restorations in the architectural facts, the methodological proposal provides a broadening of the spectrum of analysis. Which has the possibility of being used prior to practical decision making for asset protection. The review of the units of analysis revealed that the lack of continuity in government management around the heritage violates the conservation processes.

La conservación de patrimonio arquitectónico que se encuentra bajo resguardo del gobierno mexicano no ha sido considerada como una circunstancia digna de atención para las entidades encargadas del mismo. En apariencia, consideran que ha sido una tarea exitosa su labor de evitar el deterioro físico de los monumentos públicos ubicados en zonas de protección federal. En contraste a esta percepción generalizada, desde el ámbito local ha podido observarse que los cambios de administración de gobierno sólo han generado rupturas y desvinculaciones en la planeación respecto de las formas de proteger el patrimonio arquitectónico. Por ello, la presente investigación realiza una revisión puntual sobre dicha situación, evidenciando la problemática que existe en torno de la gestión gubernamental para conservar monumentos en el Centro Histórico de Morelia. El trabajo indaga en el periodo que va de 1991, cuando fue incorporado en la Lista de Patrimonio Mundial de la UNESCO, al año de 2019, donde se hizo patente un cambio de dirección en la política nacional. Con el objetivo de identificar el grado de incidencia del gobierno en las acciones relacionadas con la protección de monumentos históricos de propiedad pública, se analizan y definen las visiones políticas de las diferentes gestiones administrativas mediante la evaluación del estado físico de los inmuebles y se documenta la evolución paulatina de la visión local a favor de la conservación de los mismos. La propuesta metodológica del presente trabajo busca contrastar la voluntad política de varias administraciones con las restauraciones llevadas a cabo sobre los hechos arquitectónicos, logrando aportar un espectro de análisis más amplio. Así, se tiene posibilidad de utilizarla como base para tomar decisiones prácticas para la protección patrimonial. La revisión de las unidades de análisis reveló que la falta de continuidad en la gestión gubernamental en torno al patrimonio vulnera los procesos de conservación.

HUMANIDADES Y CIENCIAS DE LA CONDUCTA FA-M-2020-0241 Conservación arquitectónica Monumento público Visión política Agentes de decisión

Desarrollo de nanocompositos de cápside viral P22 para la terapia con profármacos enzimáticos en cáncer de mama

Development of P22 viral capsid nanocomposites for enzymatic prodrug therapy in breast cancer

Astrid Rebeca Luna Rios (2024, [Tesis de maestría])

Las estrategias actuales contra el cáncer de mama presentan limitaciones debido a la falta de selectividad, disminuyendo su efectividad. La mayoría de los fármacos, como el tamoxifeno, requieren la activación metabólica por parte de las enzimas de la familia citocromo P450 (CYP) para ejercer mayores efectos anticancerígenos. Sin embargo, la concentración del CYP es variable y baja en las células tumorales, especialmente en el cáncer de mama, lo que provoca efectos secundarios. En la terapia de activación enzimática de profármacos (EPT), las enzimas se dirigen al tumor para transformar el profármaco, lo que normalmente implica la administración de la enzima seguida del profármaco. Sin embargo, las diferencias entre la farmacocinética y farmacodinamia son un obstáculo para mejorar el tratamiento. Por lo tanto, la administración conjunta de profármaco y enzima es esencial para garantizar su interacción favorable en el tumor. Este trabajo reporta una nueva clase de nanocompositos terapéuticos basados en partículas tipo virus P22 confinando CYP, funcionalizadas superficialmente con glucosa oxidasa (GOx) que transforma la glucosa en D-glucono-δ-lactona produciendo H2O2, el aceptor final de electrones en la transformación de tamoxifeno mediado por CYP, y conjugadas con un derivado de tamoxifeno como profármaco y ligando dirigido utilizando polietilenglicol como conector. En un microambiente tumoral rico en glucosa, estos nanocompuestos pueden producir fármaco activo in situ. Se caracterizaron las propiedades fisicoquímicas y la catálisis secuencial mediada por glucosa de los nanocompositos. Los estudios in vitro demostraron una disminución en la viabilidad celular en líneas celulares de cáncer de mama ER+ y ER-. Sin embargo, la internalización celular en ausencia de glucosa mostró ser preferencial con las VLPs dirigidas en ambas líneas celulares. La administración conjunta de enzimas y profármacos con una localización mejorada de las VLPs desarrolladas después de la funcionalización del tamoxifeno, lo que sugiere el potencial de los nanocompositos desarrollados para superar los desafíos existentes de la EPT y mejorar los resultados terapéuticos con efectos secundarios reducidos.

Current treatment strategies against breast cancer have limitations due to lack in selectivity. Most drugs, such as tamoxifen, require metabolic activation by cytochrome P450 (CYP) enzymes to perform greater anticancer effects. However, the concentration of CYP varies and is low in tumor cells, especially in breast cancer, resulting in side-effects. In enzyme prodrug therapy (EPT), enzymes are targeted to the tumor cells for prodrug transformation, typically involving the sequential delivery of the enzyme followed by the prodrug. However, differences in pharmacokinetics and pharmacodynamics are a major hindrance for improving treatment. Therefore, co-delivery of prodrug and enzyme is essential to ensure their favorable interaction in tumor. This work reports a new class of therapeutic nanocomposites based on P22 virus like particles (VLPs) confining the CYP activity, surface functionalized with glucose oxidase (GOx) that transforms glucose into D-glucono-δ-lactone producing hydrogen peroxide, the final electron acceptor in the CYP-mediated transformation of tamoxifen, and together conjugated with a tamoxifen derivative as prodrug and targeting ligand using polyethylene glycol as a linker. In glucose-rich tumor microenvironment, these nanocomposites can produce active drug in situ. The physicochemical properties and sequential glucose-mediated catalysis of the nanocomposites were characterized. In vitro studies demonstrated a decrease in cell viability in both ER+ and ER- breast cancer cell lines. However, cellular internalization in the absence of glucose showed improved uptake of targeted VLPs in both cell lines. The co-delivery of enzymes and prodrug with improved localization of developed VLPs after tamoxifen functionalization, suggests the potential of developed nanocomposites to overcome the existing challenges of EPT and improve the therapeutic outcomes with reduced side effects.

VLP-P22, Citocromo P45O, Glucosa oxidasa, Tamoxifeno, Terapia de activación enzimática de profármacos VLP-P22, Cytochrome P45O, Glucose oxidase, Tamoxifen, Enzyme prodrug therapy BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA FARMACÉUTICA DISEÑO.SÍNTESIS Y ESTUDIO NUEVOS FÁRMACOS DISEÑO.SÍNTESIS Y ESTUDIO NUEVOS FÁRMACOS