5,740 research outputs found
Co-Colonizing: The Ecological Impacts of Settler Colonialism in the American Supercontinent
Nicolás’s project began with realizing that Ecology and Indigenous/Settler Colonial Studies used the same language but not the same frameworks to discuss concepts of invasion ecology and human colonization. His project aimed to synthesize his majors in Biology and Sociology and to cross-pollinate their methodologies and frameworks. His persistent and varied research, deep engagement with sources, and consultation with faculty and peers resulted in thoughtful and original research. Mark Jordan, the faculty overseeing this Senior Synthesis project wrote, “He took on a challenging topic that merged his two majors (biology and sociology) into an interdisciplinary work of his own creation that was motivated by a clear social conscience. I was particularly impressed with his ability to view fundamental scientific approaches in the lens of a critical theoretical framework from the social sciences. This paper is one of the best-written I have read in over a decade of teaching undergraduates.
Adaptive optimal operation of a parallel robotic liquid handling station
Results are presented from the optimal operation of a fully automated robotic liquid handling station where parallel experiments are performed for calibrating a kinetic fermentation model. To increase the robustness against uncertainties and/or wrong assumptions about the parameter values, an iterative calibration and experiment design approach is adopted. Its implementation yields a stepwise reduction of parameter uncertainties together with an adaptive redesign of reactor feeding strategies whenever new measurement information is available. The case study considers the adaptive optimal design of 4 parallel fed-batch strategies implemented in 8 mini-bioreactors. Details are given on the size and complexity of the problem and the challenges related to calibration of over-parameterized models and scarce and non-informative measurement data. It is shown how methods for parameter identifiability analysis and numerical regularization can be used for monitoring the progress of the experimental campaigns in terms of generated information regarding parameters and selection of the best fitting parameter subset.BMBF, 02PJ1150, Verbundprojekt: Plattformtechnologien für automatisierte Bioprozessentwicklung (AutoBio); Teilprojekt: Automatisierte Bioprozessentwicklung am Beispiel von neuen Nukleosidphosphorylase
Linearity of charge measurement in laser filaments
We evaluate the linearity of three electric measurement techniques of the
initial electron density in laser filaments by comparing their results for a
pair of filaments and for the sum of each individual filament. The conductivity
measured between two plane electrodes in a longitudinal configuration is linear
within 2% provided the electric field is kept below 100 kV/m. Furthermore,
simulations show that the signal behaves like the amount of generated free
electrons. The slow ionic current measured with plane electrodes in a parallel
configuration is representative of the ionic charge available in the filament,
after several s, when the free electrons have recombined. It is linear
within 2% with the amount of ions and is insensitive to misalignment. Finally,
the fast polarization signal in the same configuration deviates from linearity
by up to 80% and can only be considered as a semi-qualitative indication of the
presence of charges, e.g., to characterize the filament length.Comment: 17 pages, 7 figure
Generación de D-xilosa por tratamiento hidrotérmico de endocarpios de aceitunas e hidrólisis enzimática de los oligosacáridos
Se ha desarrollado un procedimiento para obtener altas concentraciones de D-xilosa partiendo de huesos fragmentados de aceituna, un material abundante en los paises del sur de Europa. El esquema operativo consistió en el tratamiento de la materia prima con agua caliente a presión (ensayando temperaturas máximas entre 195 y 225ºC, y relaciones sólido/líquido entre 1/8 y 1/3), seguido de la hidrólisis enzimática del licor con celulasas, hemicelulasas y β-glucosidasas. En la primera etapa, el trabajo a 210ºC maximizó el rendimiento de oligosacaridos en el licor (16,9 kg/100 kg materia prima) con una baja producción del inhibidor fermentativo HMF (0,25 kg/100kg materia prima). Posteriormente, la acción sinérgica de hemicelulasas y β-glucosidasas generó la mayor cantidad de D-xilosa por hidrólisis de los oligómeros. En ese contexto, y para cargas de hemicelulasas de hasta 500 U/g, se alcanzaron rendimientos de 23,4 kg de D-xilosa, 0,63 kg de L-arabinosa y 0,21 kg de D-galactosa a partir de 100kg de endocarpios de aceituna
Modeling of the hydrogen Lyman lines in solar flares
The hydrogen Lyman lines (91.2 nm < λ < 121.6 nm) are significant contributors to the radiative losses of the solar chromosphere, and they are enhanced during flares. We have shown previously that the Lyman lines observed by the Extreme Ultraviolet Variability instrument onboard the Solar Dynamics Observatory exhibit Doppler motions equivalent to speeds on the order of 30 km s−1. However, contrary to expectations, both redshifts and blueshifts were present and no dominant flow direction was observed. To understand the formation of the Lyman lines, particularly their Doppler motions, we have used the radiative hydrodynamic code, RADYN, along with the radiative transfer code, RH, to simulate the evolution of the flaring chromosphere and the response of the Lyman lines during solar flares. We find that upflows in the simulated atmospheres lead to blueshifts in the line cores, which exhibit central reversals. We then model the effects of the instrument on the profiles, using the Extreme Ultraviolet Variability Experiment (EVE) instrument's properties. What may be interpreted as downflows (redshifted emission) in the lines, after they have been convolved with the instrumental line profile, may not necessarily correspond to actual downflows. Dynamic features in the atmosphere can introduce complex features in the line profiles that will not be detected by instruments with the spectral resolution of EVE, but which leave more of a signature at the resolution of the Spectral Investigation of the Coronal Environment instrument onboard the Solar Orbiter
Diseño de una matriz de riesgos para la prevención y reducción de las amenazas ambientales por riesgo hídrico, a partir de las acciones ejecutadas en la oficina de gestión del riesgo en el periodo de la práctica social, empresarial y solidaria
Este trabajo evalúa los resultados de inspecciones que se realizaron en la ciudad de Villavicencio – Meta, que por medio de una Matriz se clasifica el nivel de riesgo al que se encuentran familias con viviendas a las rondas de ríos en esta ciudad, igualmente se analiza uno de los riesgos más importantes son las amenazas geológicas que se presentan en los alrededores de las zonas hídricas, a causa de las fuertes lluvias que fueron presentadas durante el periodo de mayo, junio y julio del año 2022 el cual se realizó la práctica social, empresarial y solidaria en la Oficina de Gestión del Riesgo, en este proceso se identificaron ciertos puntos críticos con fallas geológicas en las invasiones de las rondas de ríos o caños, en donde se generaron daños estructurales causando pérdidas económicas a la comunidad de bajos recursos, esto implicó el aumento de labores diarias las cual fueron gestionadas generando respuestas de prevención y mitigación del riesgo, estas eran dirigidas hacia la comunidad que se encontraba vulnerable al peligro natural.This work evaluates the results of inspections that were carried out in the city of Villavicencio - Meta, which by means of a Matrix classifies the level of risk to which families with homes are found in the roundabouts of rivers in this city, also analyzes one One of the most important risks are the geological threats that arise in the surroundings of the hydric zones, due to the heavy rains that occurred during the period of May, June and July of the year 2022, in which the social, business practice was carried out. and solidarity in the Risk Management Office, in this process certain critical points with geological faults were identified in the invasions of the roundabouts of rivers or pipes, where structural damage was generated causing economic losses to the low-income community, this implied the increase in daily tasks which were managed generating responses of prevention and risk mitigation, these were directed towards the com unit that was vulnerable to natural hazard.Introducción -- Planteamiento de Problema -- Objetivos -- General -- Objetivos específicos -- Justificación -- Marco teórico -- Marco conceptual -- Marco geográfico -- Marco Legal -- Metodología -- Gestión de las Visitas de inspección ocular -- Gestión de Práctica Social, empresarial y solidaria -- Visitas de inspección ocular -- Problemática en el barrio Bochica 1 -- Descripción de la visita 1 -- Recomendaciones de la visita 1 -- Problemática en el barrio Esperanza Etapa 1 -- Descripción de la visita 2 -- Recomendaciones de la visita 2 -- Problemática en el barrio Popular -- Descripción de la visita 3 -- Recomendaciones de la visita 3 -- Problemática en el Aeropuerto Vanguardia Direccional Regional Oriente Aerocivil -- Descripción de la visita 4 -- Recomendaciones de la visita 4 -- Problemática en el barrio Juan Pablo Segundo -- Descripción de la visita 5 -- Recomendaciones de la visita 5 -- Problemática en el barrio Los Comuneros -- Descripción de la visita 6 -- Recomendaciones de la visita 6 -- Problemática en el barrio Remansos de Rosa Blanca -- Descripción de la visita 7 -- Recomendaciones de la visita 7 -- Informe de Visita Inspección Ocular -- Acta de Visita -- Aporte ingenieril -- Conclusiones -- Recomendaciones -- Bibliografía
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