Rice University Graduate Research

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Morphological diversity of extracellular vesicles revealed by cryo-electron microscopy
(ASEMV/AAEV, 10/1/2022) Kapoor, Kshipra S.; McAndrews, Kathleen M.; Biswal, Lisa S.; Kalluri, Raghu
Introduction: Exosomes are extracellular vesicles 80-150 nm in diameter, containing proteins, mRNAs, microRNAs, and lipids reflecting the parent cell. While there has been an extensive characterization of the cargo incorporated in exosomes, a detailed morphological analysis of exosomes purified by various isolation techniques has not been performed. Objective: We aimed to determine the heterogeneity of exosomes morphology and if such morphological features are conserved across sample types. Methods: Our study used Cryogenic Electron Microscopy (Cryo-EM) to examine exosome size and morphology. Results: Our results revealed significant diversity in extracellular vesicle morphology independent of the isolation method, suggesting that morphological subpopulations of these vesicles exist. Based on their shape, our analysis classified exosomes into seven categories. In addition, we developed a semi-automatic image analysis framework to accurately characterize exosome attributes and distribution to facilitate reliable quantification of specific bio-nanoparticle features in Cryo-EM micrographs. Conclusions: Morphological features of exosomes inform their biophysical properties, which influence both biodistribution and biological activity in vivo. Our data demonstrating the innate morphological diversity of exosomes may have implications for improving the specificity and precision of exosome-delivered therapeutics. Conflict of interest: R.K. and MD Anderson Cancer Center hold patents in exosome biology and are stock equity holders in Codiak Biosciences Inc. R.K. is a consultant and a scientific advisor of Codiak Biosciences Inc.
Simple ultraviolet microscope using off-the-shelf components for point-of-care diagnostics.
(Rice University, 2/12/2019) Wong, Cindy; Bioengineering
At the primary care setting, where there are often no or minimal laboratories, examinations often consist of self-testing and rapid diagnostics. Because of this, medical devices must be simple, robust, and easy to operate. To address these concerns, an alternate fluorescence microscope design uses ultraviolet (UV) excitation, since fluorescent dyes that are excitable in the visible region are also excitable by UV. This may allow for the removal of typical excitation, emission, and dichroic filters as optical components absorb UV wavelengths and UV is not detected by silicon based detectors. Additionally, UV has a very low penetration into samples, which may allow for controlling the depth of excitation, and thus the imaging volume. Based on these ideas, we developed a simple fluorescence microscope built completely from off-the-shelf components that uses UV to image fluorescently stained samples. The simple opto-mechanical design of the system may allow it to be more compact and easy to use, as well as decrease the overall cost of the diagnostic device. For biological validation, we imaged whole blood stained with acridine orange and performed a two-part white blood cell differential count.
Lessons in Buffoonery and Bravado: Erik Van Lieshout
(Rice University, 2007) Hooper, Rachel; Walker Art Center
Artist entry on Erik Van Lieshout for "Brave New Worlds" catalogue
The Dizzident: Lia Perjovschi
(Rice University, 2007-10-04) Hooper, Rachel; Walker Art Center
Artist entry on Lia Perjovschi in "Brave New Worlds" catalogue
Complicated Desires: Yto Barrada
(Rice University, 2007-10-04) Hooper, Rachel; Walker Art Center
Artist entry on Yto Barrada in "Brave New Worlds" catalogue
Subtle Shifts: Artur Zmijewski
(Rice University, 2007-10-04) Hooper, Rachel; Walker Art Center
Artist entry on Artur Zmijewski in "Brave New Worlds" catalogue
Respect and Pride Restored: Zwelethu Mthethwa
(Rice University, 2007-10-04) Hooper, Rachel; Walker Art Center
Artist entry on Zwelethu Mthetwa in "Brave New Worlds" catalogue
Imprints of Conflict: Yael Bartana
(Rice University, 2007-10-04) Hooper, Rachel; Walker Art Center
Artist entry on Yael Bartana for "Brave New Worlds" catalogue
Satire and A Cynical Smile: Josephine Meckseper
(Rice University, 2007-10-04) Hooper, Rachel; Walker Art Center
Artist entry on Josephine Meckseper in "Brave New Worlds" catalogue
A Lexicon of Suburban Neologisms
(Rice University, 2008-02-16) Hooper, Rachel; Yen, Jayme; Walker Art Center
The suburbs have always been a fertile space for imagining both the best and the worst of modern social life. Portrayed alternately as a middle-class domestic utopia and a dystopic world of homogeneity and conformity--with manicured suburban lawns and the inchoate darkness that lurks just beneath the surface--these stereotypes belie a more realistic understanding of contemporary suburbia and its dynamic transformations. Organized by the Walker Art Center in association with the Heinz Architectural Center at Carnegie Museum of Art, "Worlds Away: New Suburban Landscapes" is the first major museum exhibition to examine both the art and architecture of the contemporary American suburb. Featuring paintings, photographs, prints, architectural models, sculptures and video from more than 30 artists and architects, including Christopher Ballantyne, Center for Land Use Interpretation, Gregory Crewdson, Estudio Teddy Cruz, Dan Graham and Larry Sultan, "Worlds Away" demonstrates the catalytic role of the American suburb in the creation of new art and prospective architecture. Conceived as a revisionist and even contrarian take on the conventional wisdom surrounding suburban life, the catalogue features new essays and seminal writings by John Archer, Robert Beuka, Robert Breugmann, David Brooks, Beatriz Colomina, Malcolm Gladwell and others, as well as a lexicon of suburban neologisms.
Making Waste Public
(Rice University, 2009) Gambetta, Curt; El-Dahdah, Fares
This thesis questions the boundaries that define waste as a public or private dilemma, investigating these boundaries as productive sites for the imagination of social life. Learning from methods of processing, conveyance and disposal, I investigate a number of possible sites where the architectural mediates the life of a wasted object and the social life that is produced around an engagement with that object. Waste has largely been disappeared from the city and the senses by mechanisms of modern sanitation and architecture, moved to the urban periphery and concealed inside increasingly refined membranes of storage and movement. Though ruptures or discrepancies in the waste stream are often read as signposts of failure of a certain project of the modern city, I read these ruptures or excesses as productive irritants for working and reworking how we conceptualize public space. It is within the friction of overlapping claims made to an issue such as waste that public life emerges.
Visual Displays: Developing a Computational Model Explaining the Global Effect
(Rice University, 2009) Stanley, Clayton; Byrne, Michael D.
This work aims to integrate Byrne’s theory of visual salience computation (2006) with Salvucci’s model of eye movements (2001) by testing participants on a visual search task similar to Findlay (1997). By manipulating the number, salience, and spacing of targets, participants exhibited the global effect averaging phenomena during the first recorded saccade, whereby short‐latency saccades land in between adjacent objects. Previous work has argued that the saccadic targeting system causing the averaging is influenced both by the salience and arrangement of objects displayed (Rao, Zelinsky, Hayho, & Ballard, 2002). However, to accurately account for these results, we did not have to couple the salience system with the saccadic targeting system. Instead, the systems work sequentially and in isolation, whereby the salience system simply hands off the next object to examine to the targeting system, whose accuracy depends only on saccadic latency and the location of the targeted and non‐targeted items.
Tracing the Last Breath
(Rice University, 2009) Wood, Timothy Dylan; Faubion, James D.
Anlong Veng was the last stronghold of the Khmer Rouge until the organization's ultimate collapse and defeat in 1999. This dissertation argues that recent moves by the Cambodian government to transform this site into an “historical-tourist area” is overwhelmingly dominated by commercial priorities. However, the tourism project simultaneously effects an historical narrative that inherits but transforms the government’s historiographic endeavors that immediately followed Democratic Kampuchea’s 1979 ousting. The work moves between personal encounters with the historical, academic presentations of the country’s recent past, and government efforts to pursue a museum agenda in the context of “development through tourism” policies.
A Computational Model of Routine Procedural Memory
(Rice University, 2009) Tamborello, Franklin Patrick, II; Byrne, Michael D.
Cooper and Shallice (2000) implemented a computational version of the Norman and Shallice’s (1986) Contention Scheduling Model (CSM). The CSM is a hierarchically organized network of action schemas and goals. Botvinick and Plaut (2004) instead took a connectionist approach to modeling routine procedural behavior. They argued in favor of holistic, distributed representation of learned step co-occurrence associations. Two experiments found that people can adapt routine procedural behavior to changing circumstances quite readily and that other factors besides statistical co-occurrence can have influence on action selection. A CSM-inspired ACT-R model of the two experiments is the first to postdict differential error rates across multiple between-subjects conditions and trial types. Results from the behavioral and modeling studies favor a CSM-like theory of human routine procedural memory that uses discrete, hierarchically-organized goal and action representations that are adaptable to new but similar procedures.
Induction and Intuition, on the Center for Land Use Interpretation's Metholology
(Rice University, 2009-01-01) Hooper, Rachel; Cynthia Woods Mitchell Center for the Arts at the University of Houston; Blaffer Gallery
Since 1994, The Center for Land Use Interpretation (CLUI)--a research organization based in Culver City, California--has studied the U.S. landscape, using multidisciplinary research, information processing and interpretive tools to stimulate thought and discussion around contemporary land-use issues. During a residency at the University of Houston Cynthia Woods Mitchell Center for the Arts, the CLUI established a field station on the banks of the Buffalo Bayou, revealing aspects of the relationship between oil and the landscape in Houston that are often overlooked--even by the city's residents. The CLUI's findings are presented in this volume and a concurrent exhibition at the Blaffer Gallery, titled Texas Oil: Landscape of an Industry. The book documents the CLUI's methodology in a series of interviews and includes a photographic essay on land use in Houston featuring a panoramic, foldout section and a comprehensive chronology of the CLUI's projects and publications over the past 14 years.
Now Let the Storm Break Loose
(Rice University, 2009-10-31) Hooper, Rachel; JRP|Ringier
In her photography, videos and installations, Josephine Meckseper (born 1964) sets images of political activism-photographs of demonstrations, newspaper cuttings-against twinkling consumer goods and advertising motifs. This publication concentrates on a new series of works, such as the installation "Ten High" (2007) in which silver mannequins bear anti-war slogans.
Carbon Nanotubes Filled Polymer Composites: A Comprehensive Study on Improving Dispersion, Network Formation and Electrical Conductivity
(Rice University, 2010) Chakravarthi, Divya Kannan; Barrera, Enrique V.
In this dissertation, we determine how the dispersion, network formation and alignment of carbon nanotubes in polymer nanocomposites affect the electrical properties of two different polymer composite systems: high temperature bismaleimide (BMI) and polyethylene. The knowledge gained from this study will facilitate optimization of the above mentioned parameters, which would further enhance the electrical properties of polymer nanocomposites. BMI carbon fiber composites filled with nickel-coated single walled carbon nanotubes (Ni-SWNTs) were processed using high temperature vacuum assisted resin transfer molding (VARTM) to study the effect of lightning strike mitigation. Coating the SWNTs with nickel resulted in enhanced dispersions confirmed by atomic force microscopy (AFM) and dynamic light scattering (DLS). An improved interface between the carbon fiber and Ni-SWNTs resulted in better surface coverage on the carbon plies. These hybrid composites were tested for Zone 2A lightning strike mitigation. The electrical resistivity of the composite system was reduced by ten orders of magnitude with the addition of 4 weight percent Ni-SWNTs (calculated with respect to the weight of a single carbon ply). The Ni-SWNTs - filled composites showed a reduced amount of damage to simulated lightning strike compared to their unfilled counterparts indicated by the minimal carbon fiber pull out. Methods to reduce the electrical resistivity of 10 weight percent SWNTs -- medium density polyethylene (MDPE) composites were studied. The composites processed by hot coagulation method were subjected to low DC electric fields (10 V) at polymer melt temperatures to study the effect of viscosity, nanotube welding, dispersion and, resultant changes in electrical resistivity. The electrical resistivity of the composites was reduced by two orders of magnitude compared to 10 wt% CNT-MDPE baseline. For effective alignment of SWNTs, a new process called Electric field Vacuum Spray was devised to overcome viscosity within the dispersed nanotube polymer system, and produce conductive MDPE-SWNT thin films. Polarized Raman spectroscopy and scanning electron microscopy (SEM) analysis on the samples showed an improvement in SWNT -- SWNT contacts and alignment in the polymer matrix. The resistivity of the samples processed by this new method was two order magnitudes lower than the samples processed by hot coagulation method subjected to electric field.
Stories Told in the Shape of a Sphere
(Rice University, 2010-08-28) Hooper, Rachel; Cynthia Woods Mitchell Center for the Arts at the University of Houston; Blaffer Art Museum
Amy Patton's latest film Oil slips between a theater production of Upton Sinclair's novel of the same name and the making of the film itself. Bitter, Black Thoughts is the first book on Patton's films and features her notes for Oil along with essays by curator Rachel Hooper and novelist Ingo Niermann.
Cooperative Partial Detection for MIMO Relay Networks
(Rice University, 2011) Amiri, Kiarash; Cavallaro, Joseph R.
Cooperative communication has recently re-emerged as a possible paradigm shift to realize the promises of the ever increasing wireless communication market; how- ever, there have been few, if any, studies to translate theoretical results into feasi- ble schemes with their particular practical challenges. The multiple-input multiple- output (MIMO) technique is another method that has been recently employed in different standards and protocols, often as an optional scenario, to further improve the reliability and data rate of different wireless communication applications. In this work, we look into possible methods and algorithms for combining these two tech- niques to take advantage of the benefits of both. In this thesis, we will consider methods that consider the limitations of practical solutions, which, to the best of our knowledge, are the first time to be considered in this context. We will present complexity reduction techniques for MIMO systems in cooperative systems. Furthermore, we will present architectures for flexible and configurable MIMO detectors. These architectures could support a range of data rates, modulation orders and numbers of antennas, and therefore, are crucial in the different nodes of cooperative systems. The breadth-first search employed in our realization presents a large opportunity to exploit the parallelism of the FPGA in order to achieve high data rates. Algorithmic modifications to address potential sequential bottlenecks in the traditional bread-first search-based SD are highlighted in the thesis. We will present a novel Cooperative Partial Detection (CPD) approach in MIMO relay channels, where instead of applying the conventional full detection in the relay, the relay performs a partial detection and forwards the detected parts of the message to the destination. We will demonstrate how this approach leads to controlling the complexity in the relay and helping it choose how much it is willing to cooperate based on its available resources. We will discuss the complexity implications of this method, and more importantly, present hardware verification and over-the-air experimentation of CPD using the Wireless Open-access Research Platform (WARP).
Plato, Souls, and Motions
(Rice University, 2011) Prince, Brian D.; Morrison, Donald R.
Plato’s late works contain an unexpectedly consistent treatment of the physics and metaphysics of souls. In the course of showing this, I argue that: (1) the middle period dialogues Phaedo and Republic assume, but do not mention, a Form of Soul; (2) the Timaeus contains a physical theory according to which all changes of every kind are forms of spatial motion; (3) Plato’s view of souls as self-movers is identifiable in more of his late dialogues than is usually recognized (namely, in the Statesman as well as in the Phaedrus, Timaeus, and Laws); (4) in the definition of souls as self-movers, “motion” should be read as “spatial motion” rather than “change” in general, and (5) neither the Phaedrus nor the Timaeus contains the claim that human souls are immortal, while both dialogues contain a concept of “soul-stuff,” a material from which individual souls are manufactured.

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