Reaching natural growth: Sources of variation in plant traits between indoor and outdoor experiments

One of the main problems of indoor plant production that especially plant researchers are confronted with, is a clear difference between plants grown under indoor versus outdoor conditions. This reduce the comparability between indoor and outdoor experiments as well as the portability of findings from indoor experiments to real world conditions (Matsubara, 2018). Poorter et al., (2016) suggested multiple reasons why this may occur, with major effects coming from lower light quantities, higher plant density and shorter experiment durations in indoor compared to outdoor experiments. Other sources of variation have been pointed out, including age of the plants, leaf temperature, soil temperature, soil microorganism, lack of UV light and the light quality in indoor experiments (e.g. Hogewoning et al., 2010 b). In general, the artificial conditions in indoor growth facilities often produce higher specific leaf area, leaf nitrogen content and relative growth rate, as well as lower maximum photosynthesis, plant height and shoot dry weight, compared with outdoor experiments (Poorter et al., 2016). Light, as one of of the principal determinants of plant growth and development, is consider an important source of deviation between indoor and outdoor conditions. For example, the effect of either light quantity or quantity has been well described in plants from different species, by Arnott and Mitchell (1982). To compensate a growth limitation in plants due a possible lack of light in greenhouse or indoor growth facilities, additional lighting is well stablished in agriculture, especially in areas at higher latitudes with year-round lower levels of natural sunlight (e.g. Grammans et al., 2018). Poorter et al., (2016) suggest that an important difference between indoor and outdoor climates for plant growth is a significant lower daily light integral (DLI) radiation in indoor facilities compared with outdoor conditions. Especially in combination with a lack of light variation along the day may lead to plant growth in indoor conditions that deviates considerable from field grown plants. It was not until the development and mass production of light emitting diodes (LED) that dynamic and specifics wavelengths changes as well as fast fluctuations of light intensity became possible to be used in indoor plant growth facilities. Previous attempts in plant biological research to recreate sun-like lighting with conventional light sources used very complex and fault-prone setups (e.g. Thiel et al., 1995) which were thus never widely used or considered for commercial plant production. With the technical improvements in controlled environment capabilities, the use of indoor cultivation systems has increased worldwide. In indoor experiments several authors have demonstrated the positive effects of incorporating closer-to-natural environmental conditions in indoor facilities (e.g. Arve et al., 2017, Kaiser et al., 2020,), what can help without adding higher levels of complexity to reach either closer to natural plant growth under indoor conditions and thereby increase the quality of food production to taste, smell and look more natural, attributes that are desired by consumers (Arve et al., 2017) Due to the high degree of absorption of blue (B) and red (R) light by chlorophyll, and the higher electric efficiency of LED in these spectral ranges (Overdieck, 1978), these two wavelength ranges tend to be dominating in commercial LED lamp systems (Fujiwara and Sawada, 2006). Many studies have investigated the responses of plants to different B to R ratios. These studies revealed that independent of the light intensity, a required minimum percentage of B is need for plant growth (e.g. Miao et al., 2016), and suggestions to reproduce near to natural plant growth by correctly adjusting the B:R ratio in LED lamps has been done (Hogewoning et al, 2010 a), however without directly comparing indoor grown plants with an outdoor control. In the vast majority of studies related to light quality effects on plants, either low light levels (Macebo et al., 2011; Hogewoning et al., 2010 a; Hernandez and Kubota, 2016; Kim et al., 2004; Schuerger et al., 1997) or much higher than natural red to far ratios have been use (e.g. Bae and Cho, 2008; Hogewoning et al., 2010 a; Hernandez and Kubota, 2016; Hernandez et al., 2016; Kim et al., 2004; Shengxin 2016; Zhen and van Iersel, 2017). However, interactions between light quantity and quality have been reported previously (Furuyama et al., 2014), and modifications of the light spectra, especially in the red to far ratio, has shown to induce more natural like plant growth (Hogewoning et al., 2010 b). This highlights the requirement of finding light spectral combinations in LED lighting that results in the most natural like plant growth in indoor facilities. One challenge is that different species might react differently do changes in the applied light spectrum. Tests for the effect of a light spectrum on plant performance should thus be done across different plant species (as in this thesis) in order to reveal general patterns as well as species-specific responses. In principal, lamps with multi-channel LEDs enable the application of lighting that can mimic close to natural light quality and intensities changes during plant cultivation in indoor growth facilities (Bula et al., 1991). However, although the newest generation of LED lighting systems are equipped with 4 or more individually controllable spectral channels, growth facilities generally do not apply dynamic and natural changes in the light spectra on a standard base. The knowledge about the changes in light quality related to the solar elevation angle, latitude, as well as the presence or absence of clouds (e.g. Smit, 1982; Goldberg et al., 1977) has been so far reported mainly from an atmosphere-physical point of view, and has not been transferred to actual lighting systems used for plant culture in greenhouses or growth chambers. Additionally, it has been shown that light quality effects on plants can interact with other environmental factors, like temperature (e.g. Chiang et al., 2018). This highlights the importance of understanding the role of the light quality variation on plant development, especially in order to correctly predict the effect of climate crisis on plants from indoor experiments. Although it is known that the fluctuation of environmental factors has an effect on plant phenology and development, it is common practice to apply static environmental conditions in indoor experiments. Fixed day and night time climates may be oversimplified reductions of natural conditions and may lead to plant growth significantly deviating from field grown plants (Poorter et al., 2016). Especially, it is well-known that random and daily fluctuations of temperature and light, can affect plant performance in both positive and negative ways (e.g. Myster and Moe,1995; Kaiser et al., 2015; Kaiser et al., 2018). Several studies have measured the effect of light or temperature variations on plant performance under semi-controlled and controlled conditions, but again, simultaneous comparisons with outdoor grown plants are rare in the literature and normally just Arabidopsis thaliana has been used (e.g. Vialet-Chabrand et al., 2017; Annunziata et al., 2017; Annunziata et al., 2018). Nevertheless, from these studies it could be derived that changes in light quantity along the day may induce lower biomass but also higher maxium photosynthesis, especially per unit of leaf mass (Vialet-Chabrand et al., 2017), even though fast fluctuations in light intensity have been shown to reduce photosynthesis and productivity in the long term (Kaiser et al., 2018). Additionally, these studies have shown more evidence of the difference of plants grown under totally fixed climatic conditions compared with semi-controlled environments (i.e. greenhouses), highlighting the necessity of a better knowledge for a minimum requirement of environmental fluctuations for natural like growth in indoor experiments. To investigate more closer the potential causes for the differences in plant performance between indoor and outdoor plant experiments, and to enable more natural-like plant growth in indoor facilities, a joint project had been stablish between the University of Basel (Basel, Switzerland) and Heliospectra A.B. (Gothenburg, Sweden) within the research consortia PlantHUB (European industrial doctoral programme (EID) funded by the H2020 PROGRAMME Marie Curie Actions- People), coordinated and managed by the Zurich-Basel plant science center. The project consisted of 18 months of basic research at the University of Basel, followed by 18 months of applied research, software development and documentation at Heliospectra A.B. As a result of this collaboration, the present thesis aims to identify how climatic conditions (especially, light quality and fluctuation of light intensity, temperature and air humidity) need to be adjusted in growth chambers in order to reach the most natural like plant growth under indoor conditions. To avoid documentation about only species-specific reactions, several species from different functional plant types were always used. The work on this thesis was divided in 5 main modules that aimed to: 1) Understand and quantify the natural light quality changes along the day and along a whole season, assess the effect of cloudiness on the natural light spectrum, and correlated these findings to previous studies on light quality effects in trees (Chapter 1) 2) Investigate which light spectral combination of LED-lights can induce the most natural-like growth in plants grown in indoor chambers with constant climatic conditions (Chapter 2) 3) Identify the minimal degree of environmental fluctuations (of light, temperature and air humidity) necessary to reach natural-like growth in indoor grown plants (Chapter 3) 4) Understand the effect of asynchrony environmental fluctuations in indoor growth chambers, were potential interaction and/or synergies may occur depending of the degree of variability of each environmental variable (Chapter 4) 5) Test possible applications of light fluctuations to improve crop quality and develop software applications for optimized light control of multi-wavelengths LED assimilation lamps (Chapter 5 and Appendix

Muscle synergy analysis of lower-limb movements

Dissertação de mestrado integrado em Biomedical Engineering (área de especialização em Medical Electronics)Neurological disorders and trauma often lead to impaired lower-limb motor coordination. Understanding how muscles combine to produce movement can directly benefit assistive solutions to those afflicted with these impairments. A theory in neuromusculoskeletal research, known as muscle synergies, has shown promising results in applications for this field. This hypothesis postulates that the Central Nervous System controls motor tasks through the time-variant combinations of modules (or synergies), each representing the co-activation of a group of muscles. There is, however, no unifying, evidence-based framework to ascertain muscle synergies, as synergy extraction methods vary greatly in the literature. Publications also focus on gait analysis, leaving a knowledge gap when concerning motor tasks important to daily life such as sitting and standing. The purpose of this dissertation is the development of a robust, evidence-based, task-generic synergy extraction framework unifying the divergent methodologies of this field of study, and to use this framework to study healthy muscle synergies on several activities of daily living: walking, sit-to-stand, stand-to-sit and knee flexion and extension. This was achieved by designing and implementing a cross-validated Non-Negative Matrix Factorization process and applying it to muscle electrical activity data. A preliminary study was undertaken to tune this configuration regarding cross-validating proportions, data structuring prior to factorization and evaluating criteria quantifying accuracy in modularity findings. Muscle synergies results were then investigated for different performing speeds to determine if their structure differed, and for consistency across subjects, to ascertain if a common set of muscle synergies underlay control on all subjects equally. Results revealed that the implemented framework was consistent in its ability to capture modularity (p < 0:05). The movements’ synergies also did not differ across the studied range of speeds (except one module in Knee Flexion) (p < 0:05). Additionally, a common set of muscle synergies was present across several subjects (p < 0:05), but shared commonality across every participant was only observed for the walking trials, for which much larger amounts of data were collected. Overall, the established framework is versatile and applicable for different lower-limb movements; muscle synergies findings for the examined movements may also be used as control references in assistive devices.As perturbações e traumas neurológicos afetam frequentemente a coordenação motora dos membros inferiores. Uma teoria recente em investigação neuromusculo-esquelética, denominada de sinergias musculares, tem demonstrado resultados promissores em soluções de assistência à população afetada por estes distúrbios. Esta teoria propõe que o Sistema Nervoso Central controla as tarefas motoras através de combinações variantes no tempo de módulos (ou sinergias), sendo que cada um representa a co-ativação de um grupo de músculos. No entanto, não existe nenhum processo uniformizante, empiricamente justificado para determinar sinergias musculares, porque os métodos de extração de sinergias variam muito na literatura. Para além disso, as publicações normalmente focam-se em análise da marcha, deixando uma lacuna de conhecimento em tarefas motoras do dia-a-dia, tais como sentar e levantar. O objetivo desta dissertação é o desenvolvimento de um processo robusto, genérico e empiricamente justificado de extração de sinergias em várias tarefas motoras, unindo as metodologias divergentes neste campo de estudo, e subsequentemente utilizar este processo para estudar sinergias musculares de sujeitos saudáveis em várias atividades do dia-a-dia: marcha, erguer-se de pé partir de uma posição sentada, sentar-se a partir de uma posição de pé e extensão e flexão do joelho. Isto foi alcançado através da implementação de um processo de cross-validated Non-Negative Matrix Factorization e subsequente aplicação em dados de atividade elétrica muscular. Um estudo preliminar foi realizado para configurar este processo relativamente às proporções de cross-validation, estruturação de dados antes da fatorização e seleção de critério que quantifique o sucesso da representação modular dos dados. Os resultados da extração de sinergias de diferentes velocidades de execução foram depois examinados no sentido de descobrir se este fator influenciava a estrutura dos módulos motores, assim como se semelhanças entre as sinergias de diferentes sujeitos apontavam para um conjunto comum de sinergias musculares subjacente ao controlo do movimento. Os resultados revelaram que o processo implementado foi consistente na sua capacidade de capturar a modularidade nos dados recolhidos (p < 0:05). As sinergias de todos os movimentos também não diferiram para toda a gama de velocidades estudada (exceto um módulo na flexão do joelho) (p < 0:05). Por fim, um conjunto comum de sinergias musculares esteve presente em vários sujeitos (p < 0:05), mas só esteve presente em todos os sujeitos de igual forma para a marcha, para a qual a quantidade de dados recolhida foi muito maior. Globalmente, o processo implementado é versátil e aplicável a diferentes movimentos dos membros inferiores; os resultados das sinergias musculares para os movimentos examinados podem também ser utilizado como referências de controlo para dispositivos de assistência

Programa de simulación para demolición de estructuras porticadas en concreto con utilización de explosivos

El objetivo de este trabajo es brindar a la Ingeniería Civil un programa de computador que de manera confiable, rápida y sencilla realice todos los cálculos necesarios para ejecutar una demolición con explosivos. El documento presenta información básica relacionada con los explosivos y accesorios utilizados en demoliciones, explica los conceptos y técnicas en el diseño de las voladuras y desarrolla ejemplos de diseño en forma manual para posteriormente ser comparados con los datos que arroja el programa. El software realiza todos los cálculos involucrados en la demolición de estructuras porticadas en concreto, tales como cantidad de indugel, posición de las cargas explosivas dentro de la estructura, tiempos de retardo, además de otros importantes datos, apoyado en una presentación gráfica bastante sencillaPregrad

Concentration of dimension in extremal points of left-half lines in the Lagrange spectrum

We prove that for any $\eta$ that belongs to the closure of the interior of the Markov and Lagrange spectra, the sets $k^{-1}((-\infty,\eta])$ and $k^{-1}(\eta)$, which are the sets of irrational numbers with best constant of Diophantine approximation bounded by $\eta$ and exactly $\eta$ respectively, have the same Hausdorff dimension. We also show that, as $\eta$ varies in the interior of the spectra, this Hausdorff dimension is a strictly increasing function.Comment: 24 page

Validación Empírica del Sistema Integrado de Información Financiera SIIF Nación II según el modelo de DeLone y McLean

En este trabajo se demuestra de manera empírica el éxito del Sistema Integrado de Información Financiera SIIF Nación II frente al modelo success system information de los reconocidos académicos norteamericanos DeLone y McLean, el cual da como resultado que el Sistema tiene falencias para ser exitoso, debido al incumplimiento de las dimensiones de calidad del sistema y satisfacción del usuario . Finalmente, se realizan unas recomendaciones para el mejoramiento del Sistema a la luz de la teoría de la administración pública y se realiza la salvedad que para realizar una validación del Sistema más coherente, se debe esperar el final de la vigencia 2012, como año base para determinar en una fase inicial del éxito del sistema

Estudio de movilidad peatonal: dinámicas del desplazamiento de estudiantes y empleados de la Universidad Católica de Colombia en las inmediaciones de la institución en Bogotá, Colombia

Trabajo de InvestigaciónA lo largo de la calle 47 entre carreras 13 y 16 se presenta la mayor movilidad de peatones durante la operación de la Universidad Católica de Colombia. Con este trabajo, se pretende estudiar la capacidad de servicio que tienen los andenes y el comportamiento derivado del fenómeno de interacción entre diferentes actores viales.INTRODUCCIÓN 1. MARCO DE REFERENCIA 2. METODOLOGÍA 3. RESULTADOS 4. CONCLUSIONES BIBLIOGRAFÍA ANEXOSPregradoIngeniero Civi

Guía metodológica para el levantamiento y análisis de requerimientos de software con base en procesos de negocio

Ingeniero (a) de SistemasPregrad

Madurez empresarial en gestión de proyectos en Leegs Ingeniería S.A.S

Trabajo de investigaciónCon el proyecto se desea evaluar el grado de madurez, aportar, proponer procesos de mejora para su progreso de la empresa LEEGS Ingeniería S.A.S. para lograr que sus proyectos finalicen con éxito se requiere que la empresa se conozca a sí misma, identifique los procesos, las necesidades del momento y los recursos disponibles para definir y planificar los próximos pasos que va a ejecutar a partir de su experiencia y procesos adecuados lograr superioridad en sus operaciones.Introducción 1. Generalidades 2. Marcos de referencia 3. Metodología 4. Productos a entregar 5. Entrega de Resultados Esperados e Impactos 6. Nuevas áreas de Estudio 7. Conclusiones 8. BibliografíaEspecializaciónEspecialista en Gerencia de Obras Civile

Estandarización de procesos críticos de la central de esterilización del hospital San José para sub procesos de almacenamiento y distribución según los requisitos de la NTC ISO 9001-2015 y el uso de la metodología six sigma

Auxiliar de InvestigaciónEl hospital San José cuenta con su propio centro de esterilización donde se realizan los sub procesos de lavado, empaque, esterilización, almacenamiento y distribución de instrumentos quirúrgicos o insumos, tomando para este estudio los sub procesos de almacenamiento y distribución, se aplicó la metodología six sigma partiendo desde los indicadores críticos de estos dos sub procesos para hallar el nivel sigma en el que se encontraban, se realizó un análisis detallado para así obtener como propuesta un balance score card donde se plantean estrategias para una mejora continua del proceso además de aumentar el nivel sigma de los sub procesos ya mencionados.INTRODUCCIÓN 1. GENERALIDADES 2. DEFINICIÓN DE LA PROBLEMATICA PARA LOS SUB PROCESOS DE DISTRIBUCIÓN Y ALMACENAMIENTO DEL PROCESO DE ESTERILIZACIÓN DEL HOSPITAL SAN JOSÉ. 3. MEDICIÓN DE LAS VARIABLES DE LOS SUB PROCESOS DE DISTRIBUCIÓN Y ALMACENAMIENTO 4. ANÁLISIS DE LAS VARIABLES CRÍTICAS DE LOS SUB PROCESOS DE DISTRIBUCIÓN Y ALMACENAMIENTO 5. PLAN DE MEJORAMIENTO PARA EL PROCESO DE ESTERILIZACIÓN (SUB PROCESOS DE DISTRIBUCIÓN Y ALMACENAMIENTO) 6. CONCLUSIONES 7. RECOMENDACIONES BIBLIOGRAFIAPregradoIngeniero Industria

Determinación de la capacidad ferroviaria del corredor Facatativá – Bogotá con sus características físicas actuales

Trabajo de InvestigaciónSe aborda el concepto de “capacidad ferroviaria” aplicado al corredor férreo Facatativá-Bogotá, en el cual se determina, la cantidad de trenes que pueden circular en un periodo de tiempo determinado, asumiendo ciertas características de operación como el material rodante, las paradas, tiempos de recorrido, tiempos de espera, diagramas de movilización y la velocidad media de recorrido, entre otros, de acuerdo al funcionamiento de corredores férreos similares en Colombia y a los métodos de cálculo de la “capacidad ferroviaria” de la unión internacional de ferrocarriles-UIC que es la entidad líder en la Unión Europea en la operación de las vías férreas, adaptado dichos métodos puntualmente al uso hipotético para transporte de pasajeros bajo las condiciones físicas actuales del corredor.INTRODUCCIÓN 1. GENERALIDADES 2. CAPACIDAD FERROVIARIA DEL CORREDOR FACATATIVA – BOGOTA 3. CONCLUSIONES 4. RECOMENDACIONES BIBLIOGRAFÍA ANEXOSPregradoIngeniero Civi