Biochar: for better or for worse?

This thesis presents biochar state of the art and investigations into the environmental benefits and potential impacts of biochar application to soil. Specifically, the opportunity biochar has to increase concentrations of potentially toxic elements (PTE) and polycyclic aromatic hydrocarbons (PAHs) in soil was investigated and contextualised. Results indicated limited environmental impacts in this regard. The capacity of biochar to interact with organic compounds was studied in two contexts: PAHs absorption and partitioning; and with respect to bioavailability and potential deactivation of herbicides. Regarding PAH partitioning, sewage sludge biochar (SSBC) was established to be more efficient than sewage sludge (SS) in reducing the bioaccumulation of PAHs in Lactuca satuva L. grown in contaminated soil; while increasing significantly (p < 0.05) biomass yield, relatively to a soil only control. Regarding herbicides, biochar amended soil was observed to reduce herbicide extractability (< 2%). This extractability being far lower than that observed in the biochar free control soils (40% and 90%). 14C-radiorespirometry indicated that herbicide sequestration within biochar greatly reduced its bioavailability. Biochar influence upon weed survival indicated high biochar application rates (5%) to reduce the effectiveness of herbicides, suggesting that biochar incorporation in to soil at these levels could potentially undermine agriculture that relies upon herbicides. Finally, biochar was tested as microbial carrier. Rhizobacteria survival was established to be higher in biochar produced from redwood than in peat (a common microbial carrier) at high incubation temperatures (25°C and 35°C). In conclusion, biochar addition to soil presents limited direct environmental pollution impact. While biochar absorptivity may be beneficial in mitigating the bioavailability of organic contaminants this trait needs to be considered carefully in agricultural soils where herbicides are relied upon. Given the encouraging results regarding the potential for biochar to act as a microbial inoculant carrier, further research is warranted

A Study of Dynamic Similitude for Modeling Starting Jet Vortices

Accurate numerical simulations needed for responding to coastal oil spills require a fundamental understanding of tidal eddy-driven transport. Tidal eddies are commonly formed along barrier islands and shipping channels connecting bays/estuaries to the coast. The transport in and out of the bays/estuaries controlled by these eddies is critical for many barrier island coastlines across the United States. Understanding this major form of transport can assist response efforts to disasters, such as the Texas City Y spill. In this spill, a bulk carrier collided with an oil tanker spilling 168,000 gallons of oil in the Galveston Ship Channel and was eventually stranded along the coasts of Galveston and Matagorda island. In order to improve the understanding of these tidal eddies, a shallow water flume was designed and constructed at Texas A&M University. This flume was designed based on the non-dimensional parameter space needed to describe the dynamic similitude of the behavior of coastal tidal eddies. The flume was then used to conduct surface particle image velocimetry (PIV) experiments for a 52.7 cm wide channel at 2cm, 3cm, and 5cm water depth, where the velocity information of the eddies was recorded during 5 to 10 tidal periods at different flow rates. A method was developed for designing a shallow water flume within the critical parameter space needed for dynamic and geometric similitude. The newly designed flume was then tested and the hydrodynamic conditions present for the new design were analyzed and recorded for use in future experimentation. Experiments were conducted with similar parameters to other relevant research on shallow water starting jet vortices in larger facilities to compare the results of the design process to existing data sets. The results confirm that the present experiments give dynamically similar result

New Perspectives on Intestinal Morphogenesis: The Role of Cell Division and Intraepithelial Forces in Villus Formation

Finger-like projections called villi convolute the intestinal surface, maximizing the area for nutrient absorption. Villi are rapidly formed and patterned during embryonic development; in the mouse, beginning at embryonic day (E)14.5, one new villus is defined approximately every 15 minutes. In this thesis, we worked at the interface of advanced in vivo imaging and in silico mechanical modeling to understand the transformation from a flat intestinal surface into a field of domed villi. For decades, villus morphogenesis was thought to involve formation of isolated lumens in a stratified epithelium. However, recent studies have shown that the pre-villus epithelium is a single pseudostratified layer and its surface remains connected throughout development. Here, we develop a new model that offers insight into how this dramatic lumenal surface expansion occurs within these parameters. We determined that initial villus demarcation occurs by patterned invaginations in the intestinal surface. Their location is controlled by mesenchymal clusters, patterned structures that signal to cause the adjacent epithelium to shorten and widen. This shape change compresses the intervening epithelium. Within these regions, cell division-associated invaginations occur. These in vivo observations informed an in silico mechanical model of the epithelium, which demonstrates that both compressive forces and cellular changes during mitosis can drive villus demarcation. We also utilized the Ezrin null mouse model to define other cell behavior essential for villus morphogenesis; this model exhibits both ectopic lumens and villus fusions. We show that loss of EZRIN impairs mitotic spindle orientation control and transforms the epithelium into a stratified structure. In this context, ectopic lumens form between cell layers. Additionally, we establish that Ezrin plays a critical role in maintenance of the intestinal epithelium throughout life, and provide functional evidence of impaired junctional remodeling in the absence of EZRIN. Finally, we offer a unified model of how fused villi develop embryonically and postnatally. Working at the interface between in vivo observations and in silico modeling will inform future studies on the biological and physical characteristics required for the dramatic epithelial convolution associated with villus development, potentially providing new avenues for the targeted engineering of intestinal surface.PHDCell & Developmental Biol PhDUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/144092/1/freddo_3.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144092/2/freddo_1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144092/3/freddo_2.pd

Dispersion and socio-spatial fragmentation in the recent growth of an oil city of Argentina Patagonia

La ciudad de Comodoro Rivadavia en la Patagonia argentina ha crecido históricamente de forma dispersa a partir de la localización y consolidación de los asentamientos de trabajadores en torno a las amplias áreas de explotación petrolera. El presente trabajo tiene por objetivo reconocer y caracterizar las recientes pautas de crecimiento urbano en esta ciudad recurriendo complementariamente a datos cuantitativos provenientes de fuentes oficiales, a relevamientos propios y a una técnica de observación y análisis de imágenes satelitales. Todo ello permite identificar los cambios recientes en la ocupación del espacio. Los resultados corroboran que la expansión dispersa de la ciudad tiende a profundizarse con fuertes connotaciones de fragmentación social y espacial.The city of Comodoro Rivadavia in Argentina Patagonia has grown historically dispersed from the location and consolidation of settlements of workers around the broad areas of oil exploitation. This paper aims to recognize and characterize the recent patterns of urban growth in this city using complementary to quantitative data from official sources, own surveys and a technique of observation and analysis of satellite images. This allows identify recent changes in the occupation of space. The results confirm that the dispersed expansion of the city tends to deepen with strong connotations of social and spatial fragmentation.Fil: Usach, Natalia. Universidad Nacional de la Patagonia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Freddo, Bianca Vanesa. Universidad Nacional de la Patagonia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Filling the Gap in the Classification of Phlogopite-Bearing Ultramafic Rocks

In recent years, the many new occurrences reported in the literature of ultramafic rocks that have phlogopite as a major constituent and do not fall into the categories of kimberlites, lamproites, and lamprophyres have highlighted the need for a classification that includes this abundant mineral phase. Currently, a broadly accepted classification with phlogopite does not exist, and the only term used by scientists is “phlogopite-bearing” when this phase is above 5 vol% and up to 90 vol%. For this reason, we propose a new classification that integrates phlogopite into the current classification of ultramafic rocks without modifying the already accepted terminology or the classificative criteria (i.e., the mineral modal abundances). Phlogopite is added as an end member in the ultramafic-rocks classification diagrams, changing their shapes from triangular to tetrahedral. An Excel spreadsheet containing the new diagrams and a macro that automatically classifies the rocks is provided

Vox Populi: Vernacular Politics in Early Modern Italy

This dissertation examines the rise of vernacular literary culture in Italy from the late thirteenth century to the early sixteenth century in light of concurrent political developments and reactions on the Italian peninsula. While the humanist shift from classical Latin to the use of the vernacular is often examined as a literary phenomenon, the timeline and trajectory of vernacular production evidence profound, if subtle, influences from the civic mentality of the intellectual community, particularly in Florence. This study is predominantly a work of cultural history which, in an effort to correct an oversight in the dominant historiography of civic humanism, considers the seminal function of the humanists' engagement with the vernacular. The time period studied extends from the comuni of the thirteenth and fourteenth centuries to the loss of political autonomy on the peninsula following the Italian Wars in the early fifteenth century. In broadening the conventional material and chronological parameters of the “Renaissance” and, more specifically, the questione della lingua, I construct a nuanced narrative of the innovations in civic and vernacular humanist thought which led to the ascent and formal codification of the Italian literary language in the early sixteenth century. Each chapter pairs the political lives and selected works of two prominent civic scholars from subsequent periods of Italian humanism, from Dante to Pietro Bembo; considered together, they illustrate and contextualize the critical evolutions in linguistic, political and historical thought which led to the emergence of the vernacular literary tradition as a necessary element of cultural stability, and therefore a political safeguard – first for Florence and then for the Italian peninsula at large. In exploring the intersections of linguistic issues and the politically oriented world of Italian humanism, this dissertation reassesses the place of civic thought in narratives of the vernacular literary tradition in early modern Italy

Elabora??o de um sistema de gest?o ambiental conforme requisitos de planejamento preconizados na norma ABNT NBR ISO N? 14.001/2015 em ind?stria metal?rgica de implementos agr?colas

The concern of the industries with the pollution and the excessive use of natural resources in their productive processes gains more and more importance in the organizations, highlighting the search for Environmental Management Systems (EMS) that aim to make the process sustainable and correct environmental view. In this way, this work aims to propose a methodology for the implementation of an EMS considering the requirements of the ABNT NBR ISO Standard No. 14.001 / 2015 for a metallurgical industry of agricultural implements. In view of this, an environmental policy was elaborated aiming at the objectives and principles of the company; the collection of environmental aspects and impacts in all sectors (receiving, stockpiling, machining, cutting, stamping, drilling, welding, shot blasting, painting, assembly, shipping, warehousing, administration, restaurant, auditorium, waste vehicles). These surveys highlighted the main problems faced by the industry regarding its environmental performance, and therefore, it was also carried out the survey of the legal requirements applicable to the processes. With all these data, it was possible to elaborate objectives, goals and action plans aimed at the search for continuous improvement within the productive specificities of the enterprise. It is conclude with this work that the company could improve several of its aspects in order to meet the requeriments of ISO ABNT NBR ISO 14001/2015. Good environmental management and compliance with applicable legal requirements, as a result of the search for certification of the Standard would result in an improvement in environmental performance, solid and liquid waste management, as well as better reuse of raw materials included in the process.A preocupa??o das ind?strias com a polui??o e o uso excessivo de recursos naturais em seus processos produtivos ganha cada vez mais import?ncia nas organiza??es, dando destaque para a busca de Sistemas de Gest?o Ambiental (SGA) que visam tornar o processo sustent?vel e correto do ponto de vista ambiental. Desta forma, este trabalho tem por objetivo propor uma metodologia para a implanta??o de um SGA considerando os requisitos da Norma ABNT NBR ISO n? 14.001/2015 para uma Ind?stria Metal?rgica de implementos agr?colas. Visto isso, foi elaborada uma pol?tica ambiental visando os objetivos e princ?pios da empresa; o levantamento de aspectos e impactos ambientais em todos os setores (recebimento, estoque, usinagem, corte, estamparia, fura??o, solda, jato de granalha, pintura, montagem, expedi??o, almoxarifado, administra??o, restaurante, audit?rio, central de res?duos e lavagem de ve?culos). Tais levantamentos destacaram os principais problemas enfrentados pela ind?stria quanto a seu desempenho ambiental, e por isso, foi realizado tamb?m o levantamento dos requisitos legais aplic?veis aos processos. Com todos estes dados, foi poss?vel elaborar objetivos, metas e planos de a??o voltados para a busca da melhoria cont?nua dentro das especificidades produtivas do empreendimento. Conclui-se com este trabalho que a empresa poderia melhorar diversos de seus aspectos buscando a adequa??o aos requisitos da Norma ABNT NBR ISO n? 14.001/2015. A boa gest?o ambiental e adequa??o aos requisitos legais aplic?veis, consequ?ncia da busca pela certifica??o da Norma resultaria numa melhoria do desempenho ambiental, gest?o de res?duos s?lidos e l?quidos, bem como melhor reaproveitamento de mat?rias primas inseridas no processo

Urbanización y territorio fragmentado: El mapa social de Comodoro Rivadavia–Argentina, 2010

En las últimas décadas, las discusiones sobre el hábitat se han multiplicado, alcanzando un lugar central en las reflexiones en torno a las cuestiones urbanas. La configuración espacial urbana es producto de las acciones colectivas, la aplicación de políticas públicas y la incidencia de estrategias privadas que tienden a reforzar la reproducción de las desigualdades socio-territoriales. Los mapas sociales son herramientas para el análisis, la descripción y la compresión de la heterogeneidad de los fenómenos territoriales. El presente trabajo tiene como caso de estudio la ciudad de Comodoro Rivadavia, ubicada en la Patagonia Argentina. Los objetivos son explorar las tendencias de organización y distribución del espacio urbano, a partir de los datos del Instituto Nacional de Estadística y Censos (INDEC, 2010) en diferentes niveles de desagregación espacial.In recent decades, discussions on habitat have multiplied, reaching a central place in the reflections on urban issues. Urban spatial con fi guration is the product of collective actions, the application of public policies and the incidence of private strategies that tend to reinforce the reproduction of socio-territorial inequalities. Social maps are tools for the analysis, description and understanding of the heterogeneity of territorial phenomena. The present work has as a case study the city of Comodoro Rivadavia, located in the Argentine Patagonia. The objectives are to explore trends in the organization and distribution of urban space, based on data from the National Institute of Statistics and Censuses (INDEC, 2010) at different levels of spatial disaggregation.Fil: Freddo, Bianca Vanesa. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Lavorabilità alle macchine utensili della lega Ti6Al4V formata mediante additive manufacturing

La tesi presenta l'analisi della lavorabilità alle macchine utensili di due leghe di Ti6Al4V ottenute per diversi processi di formatura, caratterizzate da diverse strutture, in particolare si compara il comportamento della lega realizzata per deformazione massiva a caldo con due leghe ottenute per Electron Beam Melting e Direct Melting Laser Sintering, impiegate largamente nel settore biomedicale. Lo scopo è di individuare le condizioni di lavorazione miglioriopenEmbargo per motivi di segretezza e/o di proprietà  dei risultati e informazioni di enti esterni o aziende private che hanno partecipato alla realizzazione del lavoro di ricerca relativo alla tes