81st Annual Seminar Day Abstracts


Aaron Ames
Bren Professor of Mechanical and Civil Engineering and Control and Dynamical Systems
Engineering and Applied Science

Toward the Robots of Science Fiction

Science fiction has long promised a world of robotic possibilities.  Achieving the promise of science fiction will require imbuing machines with the dynamic locomotion behaviors that humans display with deceptive ease—navigating everything from daily environments to uneven and uncertain terrain with efficiency and robustness.  This talk will present the first steps toward achieving this goal on bipedal and humanoid robots with the result being dynamic and efficient locomotion displaying the hallmarks of natural human walking.  The translation of these ideas to robotic assistive devices along with a wide range of safety-critical systems will be demonstrated with a view toward realizing the robots of science fiction.

Session II: 10AM
Session V: 3PM


Jack Beauchamp
Mary and Charles Ferkel Professor of Chemistry
Chemistry and Chemical Engineering

How Good Cholesterol Protects Cell Membranes from Chemical Damage

Hydroxyl radicals, also known as “nature’s detergent,” account for oxidative degradation of 90% of organic molecules released to the atmosphere from anthropogenic and natural sources.  A variety of processes also create hydroxyl radicals in vivo, where they can cause oxidative damage to molecular components of cells and tissues.  We have determined that cholesterol, typically 30 mole percent of the lipids in cell membranes, serves a non-sacrificial chemoprotective function, inhibiting the substantial chemical degradation that would otherwise occur.

Session II: 10AM
Session V: 3PM


Claire Bucholz
Assistant Professor of Geology
Geological and Planetary Sciences

Of Oxygen and Old Granites

Both the atmosphere and solid earth underwent a major transformation c. 2.4 billion years ago. Atmospheric oxygen levels rose by multiple orders of magnitude and magmatic rocks fundamentally shifted in terms of both rock type and chemistry. However, the link, if any, between these two contemporaneous transitions is not well understood. In this talk, I will present my field-based research on a unique suite of granites, which have helped reveal connections between the atmosphere and the deep earth across this critical transition in Earth’s history.

Session I: 9AM
Session IV: 2PM


Jed Buchwald
Doris and Henry Dreyfuss Professor of History
Humanities and Social Sciences

Politics, Morality, and Innovation in Physical Science and Technology

Controversy over the claims of science today roils the public sphere, particularly in the United States. This is not new. The pressures of politics, the desire to be first in innovation, moral convictions, and the potential dangers of unwitting error are all factors that have long been at work in both science and technology. We’ll examine several historical cases to better understand the dynamics that propel controversy.

Session I: 9AM
Session IV: 2PM


Bethany Ehlmann
Professor of Planetary Science
Jet Propulsion Laboratory Research Scientist
Geological and Planetary Sciences

The Story of Water on Mars

Water is essential for life as we know it, and “following the water” has been the guiding principle for NASA’s landers, rovers, and orbiters for the last decade. My group’s work focuses on learning about Mars’ environment, climate, and potential habitats for life by studying the signs of watery environments in minerals and rocks. We’ve learned that ancient Mars was much like ancient Earth around the time of life’s origins.

Session I: 9AM
Session II: 10AM


Lea Goentoro
Assistant Professor of Biology
Biology and Biological Engineering

Learning From Jellyfish

Did you know that if you tear one arm off a jellyfish, all the remaining arms will migrate around the body until the animal is symmetrical again? Or that despite having no brain, a jellyfish can apparently sleep? Jellyfish may seem remote from humans, but they have provided unexpected insights with potential implications for human health and technology: inspiring new smart materials, giving glimpses into the most ancient forms of sleep, and contributing to our dream of regenerating limbs.

Session IV: 2PM
Session VI: 4PM


Andrew Howard
Professor of Astronomy
Physics, Mathematics and Astronomy

Searching for Earth-like Planets

The search for extrasolar planets has uncovered a dizzying array of planetary systems. We have found new planet types — lava worlds and super-Earths — as well as planets orbiting more than one star.  We will tour this diverse landscape with attention to planets similar to the Earth in their size, mass, and temperature. The recent discoveries give us tantalizing clues as to how our Solar System formed and point the way to detailed characterizations of atmospheres and compositions of Earth-like worlds using the next generation of telescopes.

Session IV: 2PM
Session VI: 4PM


Mansi Kasliwal  (MS ’07, PhD ’11)
Assistant Professor of Astronomy
Principal Investigator, GROWTH (Global Relay of Observatories Watching Transients Happen)
Physics, Mathematics and Astronomy

Cosmic Fireworks

Our dynamic Universe is adorned by cosmic fireworks: energetic and ephemeral beacons of light that are a million (nova) to a billion (supernova) times brighter than our sun. On August 17, 2017, we witnessed cosmic fireworks unlike anything we had seen before. We saw two neutron stars merge and emit both gravitational waves and electromagnetic radiation spanning the gamma-rays, X-rays, ultra-violet, optical, infrared and radio. The astrophysics of the new fireworks suggests we are seeing the cocoon of a jet break out. The astrochemistry of the new fireworks suggests they serve as cosmic mines where various elements in the periodic table (e.g., Gold, Platinum, Uranium, Neodymium) are synthesized.

Session II: 10AM
Session V: 3PM


Thomas Miller
Professor of Chemistry
Chemistry and Chemical Engineering

The Extraordinary Journey:
How Proteins Get Where They’re Supposed to Go In Cells

Although proteins are synthesized only in specialized cellular locations, they are destined for delivery to all corners of the cell — and beyond. A key step in this delivery process is the efficient transport, or translocation, of the newly synthesized proteins across cell membranes, which involves a delicate balance between molecular processes. Recent studies offer high-resolution glimpses into the translocation process, but many fundamental aspects of its mechanism and regulation remain poorly understood. Miller’s presentation will focus on his lab’s efforts to computationally simulate the protein translocation process and to predict ways of controlling the targeting and delivery of proteins for therapeutic or biotechnological applications.

Session I: 9AM
Session IV: 2PM


Joseph Parker
Assistant Professor of Biology and Biological Engineering
Biology and Biological Engineering

Deceiving the Superorganism:
Infiltration of Ant Societies by Stealth Beetles

What allows a freeloading outsider to don a disguise and infiltrate a tight-knit society? Extreme evolution. By means of rapid and dramatic behavioral, anatomical, and chemical adaptations, rove beetles can assimilate into ant colonies – normally fiercely xenophobic – and exploit their social hosts undetected. This remarkable group of parasites, the most species-rich family in the animal kingdom, provides a paradigm for studying other complex symbioses.

Session I: 9AM
Session V: 3PM


Carol Raymond
Dawn Mission Principal Investigator
Jet Propulsion Laboratory

Ceres: A Unique Dwarf Planet in the Inner Solar System

Understanding how our solar system formed and where and when habitable environments existed are key questions to address the uniqueness of Earth and its life. The ion-propelled Dawn mission explored two fossils from the earliest epoch of our solar system’s history — the protoplanet Vesta and dwarf planet Ceres — to understand the conditions and processes at the dawn of our solar system. At Ceres, the mission has gathered evidence of geologic activity and clues pointing to an ancient subsurface ocean, placing Ceres in the important class of objects with astrobiological potential. This talk will present the highlights of Dawn’s 10-year exploration of the main asteroid belt and the fascinating dwarf planet Ceres.

Session II: 10AM
Session VI: 4PM


Omer Tamuz
Assistant Professor of Economics and Mathematics
Humanities and Social Sciences

The Long Run Behavior of Random Walks

Random walks have been studied for more than a hundred years as important models in physics, computer science, finance and economics, and as interesting mathematical objects in their own right. Still, many simple questions are open and are the subject of current research. I will describe some classical results, introduce random walks on groups, present some open questions regarding their long run behavior, and mention a recent result that solved a long standing problem.

Session II: 10AM
Session VI: 4PM


Lihong Wang
Bren Professor of Medical Engineering and Electrical Engineering
Engineering and Applied Science

World’s Fastest and Deepest Penetration Cameras

We developed compressed ultrafast photography (CUP) to record 10 trillion frames per second, 10 orders of magnitude faster than commercially available camera technologies. CUP can tape the fastest phenomenon in the universe, namely, light propagation, and can be slowed down for slower phenomena such as combustion. We also developed photoacoustic tomography (PAT) to peer deep into biological tissue. PAT provides in vivo omniscale functional, metabolic, molecular, and histologic imaging across the scales of organelles through organisms.

Session I: 9AM
Session IV: 2PM


Peter Westwick
Director, Aerospace History Project, Huntington-USC Institute on California and the West
The Huntington Library, Art Collections, and Botanical Gardens

Blue Sky Metropolis:
The Aerospace Century in Southern California

Southern California as we know it would not exist without aerospace. Over the twentieth century the aerospace industry transformed the region into a sprawling high-tech nexus. Southern California aerospace helped the U.S. win both World War II and the Cold War; its commercial aircraft and communications satellites enabled globalization; and its contributions to space exploration continue to challenge our imagination. Based on the Aerospace History Project, a major initiative of the Huntington-USC Institute on California and the West, this talk will survey the aerospace century, looking at the region’s influence on aerospace and aerospace influences on the region including special challenges its history poses to modern scholarship.

Session V: 3PM


Sang-Ho Yun
Geophysicist and Radar Engineer
Jet Propulsion Laboratory

Mapping Disasters from Space

Modern satellite and cloud computing technology enables rapid production of damage maps after natural disaster events. Radar sensors mounted on Earth-orbiting satellites can “see” through clouds, day and night, with high enough sensitivity to detect individual house level damage. At NASA’s Jet Propulsion Laboratory and the California Institute of Technology, we have been developing a system to automatically generate such damage maps for major earthquakes, volcanoes, landslides, wildfires, hurricanes, floods, and tornadoes.

Session I: 9AM
Session IV: 2PM


DORIS S. PERPALL SURF LECTURE SERIES WINNER

Jonathan Chan (BS ’20)
Doris S. Perpall SURF Speaking Competition
First Place

Keep it Dry

A big problem in solar desalination is the buildup of corrosive salts in the seawater channel. Superhydrophobic surfaces and carbon nanotubes can potentially repel these salts because their surface structures support an air layer in between the surface-seawater interface. Over time, however, this air layer unavoidably becomes wet due to thermodynamics, reducing the surface’s ability to repel salt. We addressed this problem by identifying irregular structures that upon being wetted, can regenerate an air layer while fully immersed underwater.

Session VI: 4PM


DORIS S. PERPALL SURF LECTURE SERIES WINNER

Juan Felipe Gomez (BS ’20)
Doris S. Perpall SURF Speaking Competition
Second Place

Exploiting the Electro-Optic Effect to Probe Topological Phase Transitions

The Pockels (Electro-Optic) Effect allows us to control the polarization of light refracted out of a crystal. We exploit this feature to turn a Pockels Cell into an optical chopper, to improve the signal-noise ratio of a pump-probe setup. Ultimately, this approach fails due to the piezo-electricity of the crystal, though the Pockels Cell can and will be used in future setups to help study novel and exotic materials.

Session VI: 4PM


GRADUATE STUDENT SPOTLIGHT TALKS

Short TED-style research presentations by graduate students chosen from a campus-wide competition will be featured. Each session will feature three different student presentations.

Sponsored by the Graduate Student Council.

Session V: 3PM

Christopher Kenseth
G3; Option: Chemistry
Chemistry and Chemical Engineering

Pulling Mountains Out of Thick Air

Throughout the Los Angeles Basin, one cannot help but notice the air. On most days, one can see the air but not the San Gabriel Mountains. By and large, airborne particles, collectively termed atmospheric aerosol, are responsible for this view-obscuring pollution that reduces our air quality, impacts our climate, and adversely effects our health. Through a combination of advanced mass spectrometric, chromatographic, and synthetic techniques, my research seeks to decipher the molecular composition, origins, and formation mechanisms of atmospheric aerosol that are essential to unraveling its impacts on climate, air quality, and health.

Nathan Stein
G3; Option: Planetary Science
Geological and Planetary Sciences

Trouble in Paradise: The Impact of Hurricane Irma on a Modern Carbonate Platform

On September 7th, 2017, the category 5 Hurricane Irma slammed into the Turks and Caicos with sustained wind speeds of 175 MPH. Sitting directly in the path of the eye was a small, low-lying, uninhabited island that was the subject of detailed drone-based mapping just one month before. The serendipitous timing of this event allowed us to probe in great deal the impact of hurricanes on carbonate platforms. I will present field observations that address several fundamental questions: what changes during powerful storms, how does the system recover, and how is it reflected in the rock record?

Anna Ho
G3; Option: Astrophysics
Physics, Mathematics and Astronomy

Stellar Detectives: Investigating the catastrophic deaths of stars

The fate of a star — how it lives, how it dies, and the corpse it leaves behind — depends primarily on its mass. High-mass stars explode as supernovae and leave behind a neutron star or a black hole. In rare cases, accretion onto the rapidly rotating black hole acts as an "engine" that launches a jet of relativistic matter. We are investigating these “engine-driven” explosions using a network of robotic telescopes around the world and in space, centered at Caltech’s Palomar Observatory. Our discoveries will teach us how matter behaves in conditions too extreme for our laboratories on Earth.


GRADUATE STUDENT SPOTLIGHT TALKS

Short TED-style research presentations by graduate students chosen from a campus-wide competition will be featured. Each session will feature three different student presentations.

Sponsored by the Graduate Student Council.

Session VI: 4PM

Josh Brake
G4; Option: Electrical Engineering
Engineering and Applied Science

Seeing through the fog

Seeing through the human body with visible light is often thought to be the stuff of science fiction. While jellyfish and a small number of other animals have transparent bodies, the tissue of the vast majority of animals is opaque to visible light, making it difficult to see deep inside their bodies. The physical principle which causes this opacity is the same principle which makes it difficult to see through fog. In this talk, I will describe our recent work to develop and apply techniques which enable us to beat this opacity and focus light deep inside opaque media like biological tissue.

Anand Muthusamy
G2; Option: Chemistry
Chemistry and Chemical Engineering

Drugs in the Brain, Inside-Out

Brain function involves precise communication within circuits of nerve cells.  When a drug—either from natural sources, or from a chemist—enters the scene, it can create specific distortions. Classical experiments show that neural drugs act by binding to their receptors on the outside of the cell membrane. But how does addiction arise from nicotine or opioid use? How do most antidepressants take weeks to work? A big hint: drugs can also enter cells. We have little data—but many ideas—about the consequences of this entry.  I discuss novel fluorescent biosensors and imaging techniques that visualize the mechanisms underlying neural drug actions.

Sofia Quinodoz
G5; Option: Biology
Biology and Biological Engineering

How is the nucleus of the cell organized similar to the city of Los Angeles? Mapping how the genome is packaged inside the cell.

Biologists have been fascinated for decades by a central question: how do 3 billion bases of DNA, spanning 6 feet end-to-end, become compacted 360,000 times to fit into a nucleus of a cell? At first glance, it must seem this immense amount of DNA is randomly shoved into each cell—much like a bowl of spaghetti. However, the ~20,000 genes in the genome are actually highly organized inside the nucleus. We find that the genome is organized around different “hubs” inside the nucleus—much like Los Angeles is organized around hubs of freeways transporting people to different locations.