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Engineering impacting social, economic and working environment

Brito, Claudio da Rocha; Ciampi, Melany M.; Vasconcelos, Rosa; Amaral, Luis; Barros, Victor Freitas de Azeredo
Fonte: American Society for Engineering Education Publicador: American Society for Engineering Education
Tipo: Artigo de Revista Científica
Publicado em /06/2013 Português
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Engineers create, design and build, bringing solutions to problems and transforming the environment for betterment of life. Engineers are responsible for the development of science and technology once they design tools, systems and instruments that make possible the acquisition of knowledge in a vast amount of fields. Engineering is responsible for the deep transformation of human relations in the first decade of the 21st century, changing also education paradigms as well as business. A new era in working environment has started, which characteristics are peculiar due to new communications, mobility and globalization. These aspects lead to the fact that now it is also important to train engineers with tools that enable them to act in a working environment that demands a very flexible and innovative mind in order to be inserted in and to keep up with the work market. Knowledge in Basic Sciences, Basic Sciences of Engineering and Specifics of Engineering are fundamental for the training of an engineer. However, the insertion in labor market sometimes demands some practice or experience that should also be provided by the engineering schools. Taking this into account, the Engineering Education Research Team of COPEC – Science and Education Research Council has designed and is implementing a program for an engineering school which main goal is to prepare engineers for the future work market...

A methodology for determining engineering costs and their effects on the development of product families

Johnson, Michael DeShawn, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 157 p.; 8973018 bytes; 8972826 bytes; application/pdf; application/pdf
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The goal of most firms is to deliver products that satisfy customer needs. Delivering a variety of differentiated products allows firms to satisfy the broadest range of customers. There is, however, a fundamental tension between this product differentiation and product cost. The use of product platforms allows a firm to reduce this tension, offering variety while also benefiting from the economics of mass production for shared components. The selection of components and subassemblies for platforming can have wide ranging effects on both product performance and cost. This thesis addresses the latter by presenting a methodology to assess product development costs, the amount of part sharing in a product family, and the effects of platforming on development, fabrication, and assembly costs for product families. Ordinal metrics are presented to assess the performance of product families. The methodology of process-based cost modeling, used to estimate product fabrication and assembly costs, is also posed. A method for determining the allocation of costs for parts and subassemblies shared among product family variants is outlined. A process-based cost model of the automotive product development process is presented. This model uses product part and subassembly characteristics to estimate the engineering effort required at various stages of the development process. Product development cycle time is also estimated. Linear regression analysis is used to determine which part and subassembly characteristics affect engineering effort. Additional development costs...

Biodegradable microfluidic scaffolds for vascular tissue engineering

Bettinger, Christopher John, 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 96 leaves; 6034088 bytes; 6045112 bytes; application/pdf; application/pdf
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This work describes the integration of novel microfabrication techniques for vascular tissue engineering applications in the context of a novel biodegradable elastomer. The field of tissue engineering and organ regeneration has been born out of the high demand for organ transplants. However, one of the critical limitations in regeneration of vital organs is the lack of an intrinsic blood supply. This work expands on the development of microfluidic scaffolds for vascular tissue engineering applications by employing microfabrication techniques. Unlike previous efforts, this work focuses on fabricating this scaffolds from poly(glycerol-sebacate) (PGS), a novel biodegradable elastomer with superior mechanical properties. The transport properties of oxygen and carbon dioxide in PGS were measured through a series of time-lag diffusion experiments. The results of these measurements were used to calculate a characteristic length scale for oxygen diffusion limits in PGS scaffolds. Microfluidic scaffolds were then produced using fabrication techniques specific for PGS. Initial efforts have resulted in solid PGS-based scaffolds with biomimetic fluid flow and capillary channels on the order of 10 microns in width. These scaffolds have also been seeded with endothelial cells and perfused continuously in culture for up to 14 days resulting in partially confluent channels. More complex fabrication techniques were also demonstrated. A novel electrodeposition technique was used in the fabrication of biomimetic microfluidic masters. Thin-walled devices were also synthesized to accommodate the relatively low gas permeability of PGS.; by Christopher John Bettinger.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

Metabolic engineering analysis of post-burn hepatic hypermetabolism

Lee, Kyongbum, 1972-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 193 p.; 14005318 bytes; 14005075 bytes; application/pdf; application/pdf
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Metabolic engineering refers to the directed improvement of product formation or cellular properties through the modification of specific biochemical reactions or introduction of new ones with the use of recombinant DNA technology. It has been used to investigate and modify intermediary metabolism in a variety of microbial organisms of biotechnological interest. An emerging area of application for metabolic engineering is medicine, in particular the study of metabolic disorders, where analysis and manipulation of metabolic pathways have obvious relevance. Central to metabolic engineering is the notion that metabolism results from the concerted and coordinated activities of biochemical pathways connected through shared intermediates in the form of common reactants, products, and catalysts. According to this "metabolic network" concept, an enhanced understanding of metabolism and cellular function is obtained by considering the component biochemical reactions together, rather than individually. In this light, this thesis work was motivated by the idea that the application of metabolic engineering analysis to biological systems relevant to human disease has the potential to provide valuable insight into the biochemical underpinnings behind metabolic disorders. In the present dissertation...

Isolation and engineering of a high affinity antibody against P-selectin glycoprotein ligand-1 (PSGL-1)

Swers, Jeffrey Seth
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 99 leaves; 5022474 bytes; 5027670 bytes; application/pdf; application/pdf
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We aim to develop novel protein antagonists of P-selectin adhesion as anti- inflammatory therapeutics. Blocking P-selectin adhesion is particularly attractive because this adhesion mediates leukocyte rolling which occurs early in the inflammatory cascade before extensive tissue damage caused by the amplification of inflammation by proinflammatory cytokines. Currently, no subnanomolar antagonists of selectin adhesion are available. The low affinity of current antagonists results in the need for frequent administration and large doses in order to obtain inhibition. High affinity antagonists are desirable because they can be administered in smaller amounts thus reducing the risk of harmful side effects and reducing production costs. Our approach for developing high affinity antagonists is to combine error prone PCR and in vivo homologous recombination to mimic in yeast the broad spectrum of mutagenic strategies exploited by B cells such as somatic hypermutation, receptor revision (... CDR replacement), receptor editing (chain shuffling), and amino acid insertions and deletions. Together with yeast surface display and flow cytometric screening (FACS), this approach has been used to effect at least a five order of magnitude affinity improvement in a single chain antibody (scFv) directed against the N-terminal 19 amino acids of P-selectin glycoprotein ligand- 1 (PSGL- 1). Three rounds of engineering were performed after an initial pool of binders was isolated from a non-immune scFv library. Chain shuffling was found to be important for generating an improved mutant in the first round of engineering.; (Cont.) For the final round of engineering...

Understanding the careers of the alumni of the MIT Mechanical Engineering department

Wolfe, Kristen E. (Kristen Elaine), 1982-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 101 leaves; 5868272 bytes; 5873919 bytes; application/pdf; application/pdf
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This research seeks to understand the careers of MIT mechanical engineering alumni. Data was collected to determine the knowledge and skills that graduates from the classes of 1992 through 1996 make use of in their professions. Data was collected on many topics in four areas: technical knowledge and reasoning, personal and professional skills and attributes, interpersonal skills, and engineering skills. The topics were ranked in terms of expected proficiency, frequency of use, and source of knowledge. The data is presented and implications for improving the mechanical engineering curriculum are discussed.; by Kristen E. Wolfe.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.; Includes bibliographical references.

Design and implementation of software to automate reuse in component-based system engineering; Software to automate reuse in component-based system engineering

Chan, Chibong
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 62 leaves; 3449977 bytes; 3451780 bytes; application/pdf; application/pdf
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The goal of this thesis is to develop software under the SpecTRM software package for the partial automation of tasks associated with reusing SpecTRM-RL component models. The automation software is designed to aid the application of component-based system engineering in SpecTRM, mainly by reducing the amount of manual work necessary in setting up component models for simulation. My thesis will examine the properties of component models, and the common tasks associated with component-based system engineering, so as to identify areas where automation is possible, and then present the user interfaces and algorithms necessary to achieve automation. The automation software will be implemented in Java under the Eclipse platform, in order to be seamlessly integrated into the SpecTRM software package.; by Chibong Chan.; Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.; Includes bibliographical references (leaf 45).

An evaluation of grain boundary engineering technology and processing scale-up

Zelinski, Jeffrey A
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 74 p.; 4340616 bytes; 4343633 bytes; application/pdf; application/pdf
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Grain boundary engineering is the manipulation of low stacking-fault energy, face- centered cubic material microstructures to break the connectivity of the general grain boundary network through the addition of special grain boundaries. Grain boundary engineering processing consists of thermomechanical cycling, i.e. repeated strain and annealing sequences and provides a method of producing more robust polycrystalline materials. This evaluation presents an introduction to the fundamental principles of grain boundary engineering, reviews the processing techniques and relevant intellectual property, analyzes the processing variables and their effect on a manufacturing line, surveys the current market and competition, and provides a preliminary cost analysis.; by Jeffrey A. Zelinski.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005.; Includes bibliographical references (p. 50-52).

The progressive synthesis of architecture and engineering in modern bridge design

Shabanowitz, Timothy B. (Timothy Brian)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 44 leaves; 14127873 bytes; 14127589 bytes; application/pdf; application/pdf
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History states that architects and engineers rarely operate in a peaceful environment as each have their own specific agendas to fulfill. The architect appeals to the plastic form of a building before tending to its structural behavior while the engineer tends towards the opposite. While both are striving for a workable structure, their priorities are mismatched. Bridge building, through history usually was considered an engineering feat as it was strictly constructed to traverse a crevasse, waterway or some other obstacle. However through the 20th century, the respective roles have evolved and bridges have become more than a mere span. The architect has revolutionized the art of building a bridge, but was it the technology of the engineer that helped propel the architect or was it just a simple awakening by the architectural community? By analyzing a variety of bridges by Santiago Calatrava and Robert Maillart among other architects and engineers that have been the most influential in this movement, and their construction process, form, materials, and design process, et al., it can be observed how the bridge building process has evolved. Bridge building is an engineering movement no more, but it is not an architectural movement either. In part...

The role of computer-aided drafting, analysis, and design software in structural engineering practice

De los Reyes, Adrian
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 103 p.; 31815672 bytes; 31815215 bytes; application/pdf; application/pdf
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Perhaps the greatest innovation in engineering in the last fifty years, computer software has changed the way structural engineers conduct nearly every aspect of their daily business. Computer-aided drafting, analysis, and design software are invaluable tools for any structural engineering firm. Given the growth, extensive competition, and demands of the industry, a firm cannot survive if it does not take advantage of the powers and capabilities that modem computer software offer. Computers have drastically altered the way engineers communicate with co-workers, clients, architects, and construction managers, improving the efficiency of the design delivery system and facilitating the conveying of design changes, issues, and concerns between all entities involved in a project. This software has optimized the structural drafting, analysis, and design processes in ways engineers never could have imagined possible half a century ago. These innovations not only add up to major savings in construction costs and increased profits for all parties involved in a project, but also to more accurate designs, quicker design completions, improved organization and sharing of data, and higher productivity within the engineering office.; (cont.) This thesis examines the applications of computer software in the structural engineering industry...

Gene-supplemented collagen-glycosaminoglycan scaffolds for nonviral gene delivery in articular cartilage tissue engineering

Capito, Ramille M. (Ramille Marie)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 260 p.
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Three-dimensional scaffolds and growth factors have been shown to be important for articular cartilage tissue engineering. A major problem in using recombinant proteins in vivo, however, is the inability to maintain therapeutic levels over prolonged times due to degradation or diffusion from the defect site. The goal of this thesis was to develop a method to employ type II collagen-glycosaminoglycan (CG) scaffolds for the nonviral delivery of the gene encoding for insulin-like growth factor (IGF)-I, as a novel means to provide a local, elevated, and prolonged release of a therapeutic growth factor via transfection of cells seeded or migrating within the scaffold. In vitro studies were performed to evaluate gene-supplemented CG (GSCG) scaffolds, including: 1) the type of expansion medium to use for growing chondrocytes prior to transfection, 2) methods of incorporating genes within scaffolds, 3) additional incorporation of transfection enhancers, and 4) the use of mesenchymal stem cells (MSCs) as an alternative cell source for articular cartilage tissue engineering.; (cont.) The medium used during monolayer expansion not only had a significant effect on subsequent biosynthesis and chondrogenesis in CG scaffolds, but also on gene transfer to chondrocyte monolayers. The expansion medium that resulted in enhanced 3-D biosynthesis and gene transfer to cells in monolayer was used throughout the rest of the studies. Greater plasmid retention within GSCG scaffolds was achieved by chemically cross-linking the plasmid IGF-1 (pIGF-1) to the scaffold (compared to simple plasmid absorption)...

Using mass media to bring engineering principles to young audiences to inspire interest and pursuit of future engineering or technologically based careers

Straub, Kimberly M; Lentz, Deanna M
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 22 leaves
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In the progression of this thesis document, an idea for an episode of an educational and interactive television show has been explored and developed. The direction of this episode will fit into the aforementioned educational television show format (which will be further described and discussed in subsequent sections of this document). For our particular episode, the focus audience and main target demographic of the theme are young, middle-school aged girls. The theme of the show, which has to do with cooking a familiar and typically well-liked (by children) food by using an alternative energy source and engineering design principles. In this show, it is our goal that both the players and the viewing audience learn about the engineering concepts involved with basic optics and solar energy. In our investigation, a theme for the episode has been developed, and a sample solution has been worked out and tested. Based on the results of this trial run, suggestions and conclusions have been made regarding the future directions for this project.; by Kimberly M. Straub and Deanna M. Lentz.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.; Includes bibliographical references (leaf 22).

Development of systematic and combinatorial approaches for the metabolic engineering of microorganisms

Alper, Hal (Hal Samuel)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 261 p.
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Explorations and optimizations through the genomic space are a daunting undertaking given the complexity and size of the possible search space. To approach this problem, systematic and combinatorial approaches were employed for the engineering of cellular phenotype in Escherichia coli. Initially, a computational method based on global cellular stoichiometry was employed to identify single and multiple gene knockout targets for lycopene production in E. coli. These targets led to substantial increases in lycopene production, but were limited in scope due to the nature of these models. Therefore, these approaches and targets were complemented with combinatorial searches to identify unknown and regulatory targets. When combined, these searches led to further increases of lycopene production and allowed for the visualization of the resulting metabolic landscape. A more exhaustive search was conducted in the background of eight genotypes which resulted in the formulation of the gene knockout search network. This network enables the investigation into how phenotype optimization is biased by search strategy.; (cont.) Collectively, these results demonstrated that despite the complexity and nonlinearity of genotype-phenotype spaces, most of the significant phenotypes were controlled and regulated by a small subset of key "gateway" nodes. Often...

Design Squad seasons 1 and 2 : an engineering perspective; Design Squad seasons one and two : an engineering perspective

Powers, Benjamin G. (Benjamin George), 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 208 p.
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This thesis describes the engineering tasks associated with production of Design Squad, a reality-based television program on WGBH. In Design Squad a client gives two teams of high school students an engineering design task for them to complete over two days of building. In order to facilitate production of this program an extensive amount of engineering preparation work is required. Tasks for each episode include concept brainstorming, prototyping of challenge solutions, material procurement, and on-set mentoring. These development and preparation activities require creative brainstorming, teamwork, and communication across a multi-disciplinary team. The MIT based engineering support team has created methods and guidelines to ensure efficient knowledge generation during prototyping that utilize sample builds, proofs of concept, and sketching. Techniques have also been developed for mentoring and guiding the cast members on set. Additionally, a wiki-based communication, tracking, and documentation tool was created to aid in the development process.; by Benjamin Powers; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.; Includes bibliographical references.

Qualitative knowledge construction for engineering systems : extending the design structure matrix methodology in scope and procedure

Bartolomei, Jason E
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 191 leaves
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This thesis presents a new modeling framework and research methodology for the study of engineering systems. The thesis begins with a formal conceptualization of Engineering Systems based upon a synthesis of various literatures. Using this conceptualization, a new modeling framework is presented called the Engineering Systems Matrix (ESM). The ESM is an improvement to existing system-level modeling frameworks, such as the Design Structure Matrix (DSM), by providing a dynamic, end-to-end representation of an engineering system. In support of this contribution, a new research methodology is presented called Qualitative Knowledge Construction (QKC). QKC can be thought of as a Bayesian-type approach to grounded theory. The methodology integrates qualitative social science with quantitative methods by developing a procedure for translating textual reports of observations, interview transcripts, system documentation, and figures into coded data represented in the ESM. The thesis develops the ESM framework and the QKC methodology in the context of a real world engineering system, a US Air Force miniature uninhabited air vehicle (MAV) product development system.; by Jason E. Bartolomei.; Thesis (Ph. D.)--Massachusetts Institute of Technology...

Synthesis and microfabrication of elastomeric biomaterials for advanced tissue engineering scaffolds

Bettinger, Christopher John, 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 252 leaves
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The subject of this thesis lies at the interface of microfabrication technology and advanced biomaterials synthesis and processing for use in designing and fabricating novel tissue engineered constructs. The unifying theme is to use micron and sub-micron fabrication strategies to form advanced tissue engineering scaffolds which are able to precisely control the microenvironment of cells. These efforts are organized into two thrusts; (1) materials synthesis and process development for microfluidic scaffold fabrication and (2) micro- and nanofabricated synthetic substratum for controlling cell function. In the first thrust, materials-specific processes for the fabrication of poly(glycerol-co-sebacate), a synthetic elastomeric biodegradable polyester, into three-dimensional, hepatocyte-seeded microfluidic constructs is discussed. Material advantages of natural proteins motivated the fabrication of next-generation microfluidic scaffolds using silk fibroin from the Bombyx mori as a bulk material. The need to combine the advantages of both natural proteins and synthetic polyesters motivated the synthesis and characterization of a new class of biodegradable elastomers termed poly(1,3-diamino-2-hydroxypropane-co-polyol sebacate) (APS). APS polymers are tunable and possess the advantages of both natural and synthetic polymers. APS polymers induce a favorable biomaterial-tissue response including reduced fibrous capsule formation and macrophage recruitment compared to PLGA. In vivo degradation half lives could be controlled to between approximately 6 and 100 wks by adjusting polymer composition and processing. The second thrust focuses on the interaction with cells and synthetically fabricated nanotopographic substrates for potential in vascularized tissue engineering applications.; (cont.) The contact guidance response of human embryonic stem cells to poly(dimethylsiloxane) (PDMS) substrates with 600 nm ridge-groove geometry and 600 ± 150 nm feature height was characterized. This motivated the study of endothelial progenitor cell function and morphology on nanofabricated PDMS substrates. Endothelial progenitor cells (EPCs) were found to exhibit increased doubling time from 16.2 ± 0.8 to 20.9 ± 1.9 h for cells grown on flat and nanotopographic substrates...

Hydrogel cell encapsulation for tissue engineering

Ling, Yibo
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 124 leaves
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The engineering of artificial tissues for restoration or replacement of organ function holds the potential to alter the landscape of medical therapeutics. In many tissue engineering approaches, cells seeded within 3D porous structures are expected to remodel into tissue-like structures. Despite significant progress, difficulties in lack of control over tissue architecture as well as vascularization continue to limit the efficacy of engineered constructs. This thesis describes work aimed at tackling these two problems. First, two techniques for generating size- and shape-controlled cell-laden hydrogels are described in the context of potential modular assembly for conferring greater control over the geometry of homotypic and heterotypic cell arrangements within engineered tissues. Then, a method for producing cell-loaded microfluidic agarose hydrogels for tissue engineering is described.; by Yibo Ling.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.; Vita.; Includes bibliographical references (leaves 116-123).

Applying engineering principles to the design and construction of transcriptional devices

Shetty, Reshma P. (Reshma Padmini)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 203 leaves
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The aim of this thesis is to consider how fundamental engineering principles might best be applied to the design and construction of engineered biological systems. I begin by applying these principles to a key application area of synthetic biology: metabolic engineering. Abstraction is used to compile a desired system function, reprogramming bacterial odor, to devices with human-defined function, then to biological parts, and finally to genetic sequences. Standardization is used to make the process of engineering a multi-component system easier. I then focus on devices that implement digital information processing through transcriptional regulation in Escherichia coli. For simplicity, I limit the discussion to a particular type of device, a transcriptional inverter, although much of the work applies to other devices as well. First, I discuss basic issues in transcriptional inverter design. Identification of key metrics for evaluating the quality of a static device behavior allows informed device design that optimizes digital performance. Second, I address the issue of ensuring that transcriptional devices work in combination by presenting a framework for developing standards for functional composition. The framework relies on additional measures of device performance...

Engineering phosphorylation-dependent post-translational protein devices

Sutton, Samantha C. (Samantha Carol)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 127 p.
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One goal underlying synthetic biology is to develop standard biological parts that can be reliably assembled into devices encoding higher-order functions. Here, I developed a framework for engineering post-translational devices, which are devices whose inner workings are modulated by non-covalent protein interactions and covalent protein modifications. To test the framework, I designed a scaffold for engineering post-translational devices in yeast, the Phospholocator, that can be used to assemble peptide parts in order to produce devices that couple upstream kinase activity to regulated nuclear translocation. I used the Phospholocator to design, build, and characterize a Phospholocator device, the Cdc28-Phospholocator, whose location is regulated by the activity of cyclin-dependent kinase Cdc28. I next engineered and tested a Fus3-Phospholocator device, whose location is regulated by the activity of the mitogen-activated protein kinase Fus3, in order to demonstrate that the Phospholocator scaffold supports the engineering of many post-translational devices. I used the Cdc28-Phospholocator to follow Cdc28 activity levels throughout the yeast cell cycle, thereby illustrating the utility of the Cdc28-Phospholocator as a tool for biological inquiry. To implement more complex functions...

Forward and inverse metabolic engineering strategies for improving polyhydroxybyrate production

Tyo, Keith E. J
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 188 p.
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Forward metabolic engineering (FME) is a rational approach to cellular engineering, relying on an understanding of the entire metabolic network to direct perturbations for phenotype improvement. Conversely, inverse metabolic engineering (IME) uses a global, combinatorial approach to identify genetic loci that are important for a given phenotype. These two approaches complement each other in a strain improvement program. FME and IME approaches were applied to poly-3-hydroxybutyrate (PHB)production in Synechocystis PCC6803 [IME] and recombinant E. coli [FME] in this thesis.IME was appropriate for Synechocystis, where metabolic regulation of the native PHB pathway was not well understood. A high throughput screening method was established by developing a staining protocol that quantitatively related nile red fluorescence to PHB content, while maintaining cell viability for both organisms. This was combined with fluorescence activated cell sorting (FACS) to screen for high PHB mutants. A Synechocystis insertion mutagenesis library was screened to identify gene disruptions that increased PHB. Two gene disruptions in proline biosynthesis and an unknown function were identified and characterized.An analogous IME study in E. coli did not find increased PHB mutants...