http://hdl.handle.net/1721.1/7898 http://hdl.handle.net/1721.1/46594 Contestational design : innovation for political activism Hirsch, Edward A., 1970- This thesis presents contestational design, a unique form of design activity whose aim is promote particular agendas in contested political arenas. I propose a framework for analyzing contestational design processes, which I then apply to two initiatives that developed communications infrastructure for activist groups. The first case study is TXTmob, an SMS-broadcast system that I developed with an ad-hoc coalition of activists to support mass mobilizations during the 2004 Democratic and Republican National Conventions. It has been used by thousands of people and has inspired new projects in both the nonprofit and commercial sectors. The second case study is Dialup Radio, a telephone-based independent media system that I developed with a civil society organization in Zimbabwe. It was intended to disseminate activist information, particularly to Zimbabwe's rural poor. Despite limited infrastructure and government restrictions, several prototypes were produced and tested in Zimbabwe. After describing each case study individually, I turn to a comparison of their respective processes and the artifacts that each produced. Examining the cases side by side, I identify a set of common issues with which contestational designers contend at various points in the design process. Finally, I describe a set of organizing principles that distinguish contestational design from other kinds of design activity. Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2008. Includes bibliographical references (leaves 134-142). http://hdl.handle.net/1721.1/46593 Microfluidic bubble logic Prakash, Manu In this thesis, I propose a new paradigm in computing where bits can simultaneously transport and manipulate materials and information. Information representation is invariably physical. Though this insight is fundamental to understanding the physical limits of computation, it has never been exploited as a scheme for material manipulation. Bringing together notions from computer science and fluid dynamics, I present a new logic family "Bubble Logic" capable of both universal computation and programmable material manipulation in an all-fluidic two-phase system. This removes the distinction between materials and mechanisms to control them, bringing the programmability of the digital world into the physical world - with a wide range of promising applications in biotechnology, highthroughput screening, genomics and fluidic control systems for soft robotics, printing and digital fabrication.Microfluidics, the art of handling nano-to pico-liter volume fluids, is leading to a revolution in large-scale automation of biology and analytical chemistry. However, current lab-on-chip technologies are dependent on external macro-scale control elements, thus requiring a lab to run the chip. Bubble logic provides a dropletel,internal, inherently digital flow control mechanism at kHz frequencies with no moving parts or off-chip components. Nonlinearity is introduced in an otherwise linear, reversible, low Reynolds number flow via bubble-tobubble hydrodynamic interactions. I demonstrate bubble logic AND/OR/NOT gates, a toggle flip-flop, a ripple counter, a timing restoration device, a ring oscillator, a bistable valve and an on-demand bubble generator. These show the nonlinearity, gain, bistability, synchronization, cascadability, feedback and programmability required for scalable universal computation and control. (cont.) The representation used in this thesis makes possible encapsulation and manipulation of a large variety of micro-to nanocale materials including single molecules like DNA or proteins, live cells, liquid crystals, nano-particles and other biological and chemical reagents. Bubble logic provides a scheme to transport, store and operate on this new class of "digital materials" in an integrated, high-throughput fashion. Furthermore, microfluidics has also been extensively employed in biological systems. This thesis describes the discovery of two new physical fluid dynamic mechanisms motivated by a common theme of microfluidics in biology. Firstly, I describe a new superhydrophobic waterrepelling surface that has a characteristic of directional anisotropy to fluid resistance. The discovery, made while studying the integument of water-walking insects, helps rationalize the origin of thrust and hence propulsion of water-walking insects on a fluid interface. Secondly, this thesis uncovers a new physical mechanism for directed droplet transport, which I term "Capillary ratchet". Discovered in a class of surface feeding shorebirds, it is the only physical mechanism that is known to exploit contact angle hysteresis for fluid transport. Capillary ratchet is a promising candidate for implementing global clocking for integrated microfluidic devices. Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2008. "September 2008." Includes bibliographical references. http://hdl.handle.net/1721.1/46425 The computer as a projective medium : a descriptive analysis of children's use of an animation program for learning style Imholz, Susan C Thesis (Ph. D.)--Massachusetts Institute of Technology, Program in Media Arts & Sciences, 1993. Includes bibliographical references. http://hdl.handle.net/1721.1/45755 Microfluidic gene synthesis Kong, David Sun, 1979- The ability to synthesize custom de novo DNA constructs rapidly, accurately, and inexpensively is highly desired by researchers, as synthetic genes and longer DNA constructs are enabling to numerous powerful applications in both traditional molecular biology and the emerging field of synthetic biology, from the synthesis of large sets of novel proteins to the complete re-writing of bacterial genomes. However, the current cost of de novo synthesis--driven largely by reagent and handling costs-is a significant barrier to the widespread availability of such technology. The use of microfluidic technology greatly reduces reaction volumes and corresponding reagent and handling costs. Additionally, microfluidic technology enables large numbers of complex reactions to be performed in parallel, while facilitating the automation and integration of multiple processes in a single device. While microfluidic devices have been used to miniaturize a variety of chemical and biological processes, the benefits of such devices have yet to be realized in the area of de novo DNA synthesis. This thesis reports the first demonstration of gene synthesis in a microfluidic environment. A variety of DNA constructs with sizes as large as 1 kb were fabricated in parallel in a multi-chamber microfluidic device at volumes one to two orders of magnitude lower than those utilized in conventional bench top techniques. This thesis also reports on progress toward the direct synthesis of genes from hybrid microfluidic-DNA microarray devices, the integration of microfluidic gene synthesis with on-chip protein synthesis, and the microfluidic hierarchical synthesis of long DNA molecules. Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2008. "June 2008." Includes bibliographical references.