228 research outputs found
Expression, purification, and antifungal activity of the Epichloë festucae antifungal protein Efe-AfpA
No full textThe Class I Clavicipitaceous endophyte Epichloё is a genus of fungi that infects many turfgrasses, resulting in a variety of benefits for the grass host. Besides the anti-herbivory compounds produced and the altered physiology of the grass, Epichloё festucae has been shown to provide fungal disease resistance, a unique benefit of its association with the grass host Festuca rubra. Specifically, E. festucae infection of F. rubra provides resistance to dollar spot disease caused by Clarireedia jacksonii, a very detrimental disease of turfgrasses.Previous research identified an abundant E. festucae antifungal protein, Efe-AfpA, expressed in the infected plants. This led to the hypothesis that the antifungal protein was important in the observed disease resistance. Laboratory tests showed that the endophyte produced anti-fungal protein Efe-AfpA caused inhibition of Clarireedia jacksonii growth in culture.
The goal of this thesis is to determine the efficacy of the antifungal protein Efe-AfpA against multiple plant pathogenic fungi, with a particular focus on dollar spot disease. To determine this, multiple expression systems were tested for the most efficient way to produce pure Efe-AfpA with a high yield. The expression systems used were bacterial (Escherichia coli), yeast (Pichia pastoris), and fungal (Penicillium chrysogenum). The proteins produced from these systems were tested for inhibitory activity against Neurospora crassa conidia. Of the three tested, the P. chrysogenum system produced the highest quantity of active and easily purifiable Efe-AfpA. Once an expression system was chosen, large amounts of Efe-AfpA were purified and tested on dollar spot inoculated plants. Treatment with Efe-AfpA resulted in reduced dollar spot symptoms on endophyte free F. rubra and on creeping bentgrass (Agrostis stolonifera). These results support the hypothesis that Efe-AfpA is a factor in the observed disease resistance of E. festucae-infected F. rubra.
Antifungal proteins produced by fungi are known to have activity against a wide variety of fungi. Plant pathogens were collected from multiple laboratories in the Plant Biology Department at Rutgers University to further determine the repertoire of fungi that Efe-AfpA has activity against. The ascomycetes Botrytis cinerea, Colletotrichum cereale, Fusarium graminearum PH1, Cryphonectria parasitica, and Pyricularia oryzae are all sensitive to Efe-AfpA. Of the basidiomycetes tested, Laetisaria fuciformis and Rhizoctonia solani, only L. fuciformis had a slight sensitivity to the antifungal protein. The findings of this research may be utilized to develop Efe-AfpA as an antifungal product that could supplement and or alleviate the usage of chemical fungicides for the control of fungal disease of plants.Ph.D.Includes bibliographical reference
Modeling and Intelligent Control for Spatial Processes and Spatially Distributed Systems
Get PDFDynamical systems are often characterized by their time-dependent evolution, named temporal dynamics. The space-dependent evolution of dynamical systems, named spatial dynamics, is another important domain of interest for many engineering applications. By studying both the spatial and temporal evolution, novel modeling and control applications may be developed for many industrial processes. One process of special interest is additive manufacturing, where a three-dimensional object is manufactured in a layer-wise fashion via a numerically controlled process. The material is printed over a spatial domain in each layer and subsequent layers are printed on top of each other. The spatial dynamics of the printing process over the layers is named the layer-to-layer spatial dynamics.
Additive manufacturing provides great flexibility in terms of material selection and design geometry for modern manufacturing applications, and has been hailed as a cornerstone technology for smart manufacturing, or Industry 4.0, applications in industry. However, due to the issues in reliability and repeatability, the applicability of additive manufacturing in industry has been limited. Layer-to-layer spatial dynamics represent the dynamics of the printed part. Through the layer-to-layer spatial dynamics, it is possible to represent the physical properties of the part such as dimensional properties of each layer in the form of a heightmap over a spatial domain. Thus, by considering the spatial dynamics, it is possible to develop models and controllers for the physical properties of a printed part. This dissertation develops control-oriented models to characterize the spatial dynamics and layer-to-layer closed-loop controllers to improve the performance of the printed parts in the layer-to-layer spatial domain.
In practice, additive manufacturing resources are often utilized as a fleet to improve the throughput and yield of a manufacturing system. An additive manufacturing fleet poses additional challenges in modeling, analysis, and control at a system-level. An additive manufacturing fleet is an instance of the more general class of spatially distributed systems, where the resources in the system (e.g., additive manufacturing machines, robots) are spatially distributed within the system. The goal is to efficiently model, analyze, and control spatially distributed systems by considering the system-level interactions of the resources. This dissertation develops a centralized system-level modeling and control framework for additive manufacturing fleets.
Many monitoring and control applications rely on the availability of run-time, up-to-date representations of the physical resources (e.g., the spatial state of a process, connectivity and availability of resources in a fleet). Purpose-driven digital representations of the physical resources, known as digital twins, provide up-to-date digital representations of resources in run-time for analysis and control. This dissertation develops an extensible digital twin framework for cyber-physical manufacturing systems. The proposed digital twin framework is demonstrated through experimental case studies on abnormality detection, cyber-security, and spatial monitoring for additive manufacturing processes. The results and the contributions presented in this dissertation improve the performance and reliability of additive manufacturing processes and fleets for industrial applications, which in turn enables next-generation manufacturing systems with enhanced control and analysis capabilities through intelligent controllers and digital twins.PhDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/169635/1/baltaefe_1.pd
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Daughter of fortune: Isabel Allende's popularity from a readership perspective
No full textThe primary aim of this thesis is to explore and critically interrogate Isabel Allende’s popularity cross-culturally in Britain and Spain. It analyses readers’ responses to Allende’s works as well as the discourses surrounding her public representation, an approach that is ‘readerly’ but must also take account of production and text. This approach is intended to further the understanding of Allende’s work which so far has always been analysed from a textual perspective. However, the relationship between Allende’s popularity, her texts, public representation and readers has not been yet analysed in detail.This thesis is innovative in other ways too. Methodologically, it approaches readers through the under studied cultural form of the reading group. It also incorporates a comparative dimension by looking at the reception of Allende in two different cultural contexts: the British and Spanish respectively. Finding out about Allende’s popularity has involved asking readers about their reading experiences as well as analysing the production of discourses around her public representation. Paul Ricoeur’s (1984, 1988) perspective on authorial intentions and readers’ responses to texts helps in understanding the intricacies surrounding what is involved in reading any text. It draws attention to Allende’s and her publishers’ authorial strategies, her ‘strategies of persuasion’ and the specificity of the lives and contexts of British and Spanish reading publics. Equally, this ‘readerly’ approach draws on feminist audience research and primarily on the work of Ien Ang and Janice Radway. Their work with viewers and readers respectively is particularly useful in establishing and developing methodological parameters for the study of reading groups. As a whole, this thesis contributes to the understanding of Allende’s cross-cultural popularity by situating readers at the centre
Association between cribbing and entrapment of the small intestine in the epiploic foramen in horses: 68 cases (1991-2002)
No full textObjective - To determine whether there was an association between a history of cribbing and epiploic foramen entrapment (EFE) of the small intestine in horses. Design - Retrospective study. Animals - 68 horses examined at the University of Illinois or the University of Liverpool veterinary teaching hospitals. Procedure - For horses examined at the University of Illinois that underwent surgery because of strangulating small intestine lesions, information about cribbing was obtained through telephone calls with owners. For horses examined at the University of Liverpool that underwent surgery for colic for any reason, information about cribbing was obtained through a preoperative questionnaire. Results - 13 of 19 (68%) horses with EFE examined at the University of Illinois had a history of cribbing, compared with only 2 of 34 (6%) horses with other strangulating small intestine lesions (odds ratio, 34.7; 95% confidence interval, 6.2 to 194.6). Similarly, 24 of 49 (49%) horses with EFE examined at the University of Liverpool had a history of cribbing, compared with 72 of 687 (10.5%) horses with colic caused by other lesions (odds ratio, 8.2; 95% confidence interval, 4.5 to 15.1). Conclusions and Clinical Relevance - Results suggest that there may be an association between cribbing and EFE in horses, with horses with a history of cribbing more likely to have EFE than horses without such a history
Robotics and manufacturing automation
No full textManufacturing automation is vital to various industrial sectors: aeronatic, automotive, biomedical, consumer goods, and others. Two main trends influence the develepment in manufacturing automation: the large availability of data, reflecting the environment and the manufacturing process, and the emergence of robotics-based systems, and in general, robotics as a framework for autonomous systems. Both trends impose the integration of more powerful and adaptive control and optimization approaches, enabling new functionality and new business models. This new generation of controllers unifies data-driven, predictive, and learning-based methods making use of the available data, and of the increased computation possibilities due to cloud connectivity and access to better hardware in general. Availability of data and computation capabilities aligns in the concept of digital twin, a living virtual replica of the industrial system, which enables flexible and economically viable approaches to monitoring, predictive maintenance, and individualized production, and more efficient means to control the manufacturing systems
Informal Open Spaces Designed by Water
No full text“Although the process of formalization is the dominant trend in modern social life, informality is the essential element in constructing trust relationships and, thus, in any cooperative arrangement aimed at improving the quality of life. [...] Only a society that achieves an optimal balance between informality and formality of interactional practices is in position to create the conditions to cooperation and innovation»1.
Water has accompanied both man’s life and landscape conformation, setting the rhythm of their changes and evolution and answering practical and symbolic needs. In this way it became an element of comunication or separation, means of defense but also possible source of danger.
Life and man cannot be without it yet they need to protect themselves from it.
Water thanks to its nature becomes promoter of human relations and artifice of different places (dockings along sea or river borders, terrace on water, places for recreation, places for rest, pauses inside cities...). If on one hand its role of basic common good has always been recognized, in modern times even entering everyday life on an individual level, on the other the presence of water in public open space, that in the beginning of the past century was regarded more as a threat and an obstacle to city expansion, losing its old aggregative and social character, nowadays it becomes renovating resource for urban requalification re-considering, re-interpreting and re-inventing its presence.
This new role is assigned to water because it’s able to ignite unique possibilities of relation and use linked mainly, but not only, to evocative and symbolic qualities and also to functional and ludic values of this extraordinary element, since interacting with water it’s an informal and collective activity.
Architectural elements of the project in contact with water aren’t really answering to a function but to an use/experience that man can have with it. The design of these elements changes the use of space and consequently the way to live places of the cities, offering new possibilities linked to an informality made by the presence of this element.
If in architecture the use of water as actual construction material is clear (as Carlo Scarpa2 used it), grasping its potential gets more difficult when it becomes actively part of the space3 entrusted to the architectural design that will shape its features providing it with an informality that is necessary to render the place inhabitable and inhabitated.
1. Barbara A. Misztal. 1999. Informality: Social Theory and Contemporary Practice. London: Biddles Ltd.
2.«Scarpa lavorava l'acqua, lavorava la luce, lavorava le superfici dei soffitti a stucco lucido con piani fra loro inclinati per ottenere un certo riverbero dovuto al movimento della luce e dell'acqua e all'intersezione dei piani» R. Giovanardi, Carlo Scarpa e l'acqua, Cicero, Venezia, 2006. [Scarpa worked water, worked light, worked ceiling surfaces with polished plaster thanks to inclined planes, to obtaine some reverb due to light and water movement and to intersection of planes] Author translation.
3.(Raum): «it’s acting-and making space that speaks in the word space. This means to make a clearing, to consolidate. To make space brings freedom, openness for man to settle in and live in [...] to make space is to make a free gift of places. It is a happening that speaks and is hidden at the same time in making space» Heidegger, M., (1969). Die kunst der Raum, St. Gallen: Erker Verlag. (trad. It. Heidegger, M. (2000). L’arte e lo spazio. Genova: Il nuovo melangolo
Robotics and manufacturing automation
No full textManufacturing automation is vital to various industrial sectors: aeronatic, automotive, biomedical, consumer goods, and others. Two main trends influence the develepment in manufacturing automation: the large availability of data, reflecting the environment and the manufacturing process, and the emergence of robotics-based systems, and in general, robotics as a framework for autonomous systems. Both trends impose the integration of more powerful and adaptive control and optimization approaches, enabling new functionality and new business models. This new generation of controllers unifies data-driven, predictive, and learning-based methods making use of the available data, and of the increased computation possibilities due to cloud connectivity and access to better hardware in general. Availability of data and computation capabilities aligns in the concept of digital twin, a living virtual replica of the industrial system, which enables flexible and economically viable approaches to monitoring, predictive maintenance, and individualized production, and more efficient means to control the manufacturing systems
Numerical and experimental analysis of bead cross-sectional geometry in fused filament fabrication
No full textPurpose This paper aims to develop experimentally validated numerical models to accurately characterize the cross-sectional geometry of the deposited beads in a fused filament fabrication (FFF) process under various process conditions. Design/methodology/approach The presented numerical model is investigated under various fidelity with varying computational complexity. To this end, comparisons between the Newtonian, non-newtonian, isothermal and non-isothermal computational models are presented for the extrusion of polylactic acid material in an FFF process. The computational model is validated through an experimental study on an off-the-shelf FFF printer. Microscope images of experimentally printed FFF bead cross-sections corresponding to various printing conditions are digitally processed for the validation. In the experimental study, common practical printing conditions for an FFF process are tested, and the results are compared to the numerical model. Findings Microscope image analyses of the cross-sectional geometries of deposited beads show that the numerical model provides a precise characterization of the cross-sectional geometry under varying process parameters in terms of the cross-section outline, bead height and width. The results show that the nozzle-to-table distance has a great effect on the bead shape when compared to the extrusion rate at a given nozzle-to-table distance. Comparison of the various computational models show that the non-Newtonian isothermal model provides the best tradeoff between computational complexity and model accuracy. Originality/value The authors provide detailed computational models, including the extruder nozzle geometry for cases ranging from Newtonian isothermal models to non-Newtonian non-isothermal models with experimental validation. The validation study is conducted for practical process parameters that are commonly used in FFF in practice and show that the computational models provide an accurate depiction of the true process outputs. As the developed models can accurately predict process outputs, they can be used in further applications for process planning and parameter tuning
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