High School Students Visit for Women in STEM Preview Day

On Friday, August 7, 104 female high school seniors and their families visited Caltech for the fourth annual Women in STEM (WiSTEM) Preview Day, hosted by the undergraduate admissions office. The event was designed to explore the accomplishments and continued contributions of Caltech women in the disciplines of science, technology, engineering, and mathematics (STEM).

The day opened with a keynote address by Marianne Bronner, the Albert Billings Ruddock Professor of Biology and executive officer for neurobiology. Bronner, who studies the development of the central nervous system, spoke about her experiences in science and at Caltech.

"Caltech is an exciting place to be. It's a place where you can be creative and think outside the box," she said. "My advice to you would be to try different things, play around, and do what makes you happy." Bronner ended her address by noting the pleasure she takes in mentoring young scientists, and especially young women. "I was just like you," she said.

Over the course of the day, students and their families attended panels on undergraduate research opportunities and participated in social events where current students shared their experiences of Caltech life. They also listened to presentations from female scientists and engineers of the Jet Propulsion Laboratory.

"I really love science, and it's so exciting to be around all of these other people who share that," says Sydney Feldman, a senior from Maryland. "I switched around my whole summer visit schedule to come to this event and I'm having such a great time."

The annual event began four years ago with the goal of encouraging interest in STEM in high school women and ultimately increasing applications to Caltech by female candidates. In 2009, a U.S. Department of Commerce study showed that women make up 24 percent of the STEM workforce and hold a disproportionately low share of undergraduate degrees in STEM fields.

"Women are seriously underrepresented in these fields," says Caltech admissions counselor and WiSTEM coordinator Abeni Tinubu. "Our event really puts emphasis on how Caltech supports women on campus, and we want to show prospective students that."

This year, the incoming freshman class is a record 47 percent female students. "This is hugely exciting," says Jarrid Whitney, the executive director of admissions and financial aid. "We've been working hard toward our goal of 50 percent women, and it is clearly paying off thanks to the support of President Rosenbaum and the overall Caltech community."

Home Page Title: 
Women in STEM Preview Day
Listing Title: 
Women in STEM Preview Day
Writer: 
Exclude from News Hub: 
No
News Type: 
In Our Community

Science for the Community

On the grounds of San Marino's Huntington Library, Art Collections, and Botanical Gardens—to the north of the Chinese Gardens, in the private, half-acre Huntington Ranch area—nearly two dozen middle- and high-school students have been spending this summer measuring the levels of nitrogen in the soils around them to help the ranch determine whether its soil is up to the challenge of growing an urban garden.

This hands-on research experience is part of the Community Science Academy @ Caltech, which is affiliated with Caltech's Center for Teaching, Learning, and Outreach (CTLO). The 23 first-timers in what is called CSA 1 are studying biological systems at the ranch; a similar number of continuing students, in CSA 2, are studying engineering and programming, and are building their own scientific instruments.

The program runs three days a week for six weeks. For CSA 1 students, it began on June 15 with soil sampling; by July 24, when it ends, students will have designed and performed their own experiments.

CSA@Caltech is now in its second year. It initially was funded with support from a National Institutes of Health Director's Pioneer Award to Caltech Professor of Biology Bruce Hay. In addition, the Pasadena Educational Foundation and the Siemens Foundation currently provide support for scholarships that allow all students from the Pasadena Unified School District to attend the program free of charge.

The students start most days with lectures by members of the Caltech staff. Every student is issued an iPad and keyboard for note taking and fieldwork. This technology allows the lectures to become interactive presentations using software that allows constant feedback between teacher and student. They spend much of their time at the CTLO on the Caltech campus, for talks on topics including soil and water quality, pest control, environmental monitoring, and remote sensing. They also work in the undergraduate teaching labs in Caltech's Divisions of Chemistry and Chemical Engineering and Biology and Biological Engineering for lessons on plant processing and bacterial detection, respectively.

At the Huntington Library, students apply in an outdoor setting what they have learned and practiced in Caltech classrooms and labs. For example, they gather soil samples from gardens and water samples from lily ponds for nitrate and ammonia testing; they conduct experiments on ant behavior; and they design and build sensor-carrying remote-controlled powered kites, which they fly over the Library grounds.

"These hands-on methods are critical for teaching students about the collaborative nature of science, the system of trial and error, and the importance of following protocols in scientific experimentation and analysis," says James Maloney (MS '06), one of the two codirectors of the CSA@Caltech program. Even while the students are getting what may well be their first exposure to research, they are also making a serious contribution to the Huntington's understanding of the ranch's viability as an urban garden. The ranch was originally a gravel parking lot, notes ranch coordinator Kyra Saegusa. It took six years for the soil to be rebuilt with sheets of mulch. The question now is whether it is ready for growing fruits and vegetables.

If the shouts of "I got a worm!" from one 13-year-old field worker are any indication, the soil restoration is certainly moving in the right direction.

The ultimate goal of CSA@Caltech—to promote STEM (science, technology, engineering, and mathematics) in secondary education and to help create the next generation of scientists—is further buttressed by tours of Caltech labs, where researchers such as Sarah Reisman, professor of chemistry, talked to the CSA@Caltech students about life as a scientist. Some of the students have already chosen areas in which they think they would like to specialize: for instance, Eris, a ninth grader from Blair High School in CSA 2, wants to study engineering and chemistry; Brandon, a CSA 2 ninth grader from Pasadena High School, wants to go into theoretical physics; and CSA 1 student Connor, an eighth grader from Sierra Madre Middle School, wants to be an aerospace engineer.

Building on this success, CSA@Caltech plans to add a third year of study next summer and continue their development of new educational technologies. "Our goal is to make high-quality science accessible to all," says CSA@Caltech codirector Julius Su (BS '98, BS '99, PhD '07).

Writer: 
Exclude from News Hub: 
No
News Type: 
In Our Community

$100 Million Gift from Gordon and Betty Moore Will Bolster Graduate Fellowships

Trustees Gordon (PhD '54) and Betty Moore have pledged $100 million to Caltech, the second-largest single contribution in the Institute's history. With this gift, they have created a permanent endowment and entrusted the choice of how to direct the funds to the Institute's leadership—providing lasting resources coupled with uncommon freedom.

"Those within the Institute have a much better view of what the highest priorities are than we could have," Intel Corporation cofounder Gordon Moore explains. "We'd rather turn the job of deciding where to use resources over to Caltech than try to dictate it from outside."

Applying the Moores' donation in a way that will strengthen the Institute for generations to come, Caltech's president and provost have decided to dedicate the funds to fellowships for graduate students.

"Gordon and Betty Moore's incredibly generous gift will have a transformative effect on Caltech," says President Thomas F. Rosenbaum, holder of the Institute's Sonja and William Davidow Presidential Chair and professor of physics. "Our ultimate goal is to provide fellowships for every graduate student at Caltech, to free these remarkable young scholars to pursue their interests wherever they may lead, independent of the vicissitudes of federal funding. The fellowships created by the Moores' gift will help make the Institute the destination of choice for the most original and creative scholars, students and faculty members alike."

Further multiplying the impact of the Moores' contribution, the Institute has established a program that will inspire others to contribute as well. The Gordon and Betty Moore Graduate Fellowship Match will provide one additional dollar for every two dollars pledged to endow Institute-wide fellowships. In this way, the Moores' $100 million commitment will increase fellowship support for Caltech by a total of $300 million.

Says Provost Edward M. Stolper, the Carl and Shirley Larson Provostial Chair and William E. Leonhard Professor of Geology: "Investigators across campus work with outstanding graduate students to advance discovery and to train the next generation of teachers and researchers. By supporting these students, the Moore Match will stimulate creativity and excellence in perpetuity all across Caltech. We are grateful to Gordon and Betty for allowing us the flexibility to devote their gift to this crucial priority."

The Moores describe Caltech as a one-of-a-kind institution in its ability to train budding scientists and engineers and conduct high-risk research with world-changing results—and they are committed to helping the Institute maintain that ability far into the future.

"We appreciate being able to support the best science," Gordon Moore says, "and that's something that supporting Caltech lets us do."

The couple's extraordinary philanthropy already has motivated other benefactors to follow their example, notes David L. Lee, chair of the Caltech Board of Trustees.

"The decision that Gordon and Betty made—to give such a remarkable gift, to make it perpetual through an endowment, and to remove any restrictions as to how it can be used—creates a tremendous ripple effect," Lee says. "Others have seen the Moores' confidence in Caltech and have made commitments of their own. We thank the Moores for their leadership."

The Moores consider their gift a high-leverage way of fostering scientific research at a place that is close to their hearts. Before he went on to cofound Intel, Gordon Moore earned a PhD in chemistry from Caltech.

"It's been a long-term association that has served me well," he says.

Joining him in Pasadena just a day after the two were married, Betty Moore became active in the campus community as well. A graduate of San Jose State College's journalism program, she secured a job at the Ford Foundation's new Pasadena headquarters and also made time to come to campus to participate in community activities, including the Chem Wives social club.

"We started out at Caltech," she recalls. "I had a feeling that it was home away from home. It gives you a down-home feeling when you're young and just taking off from family. You need that connection somehow."

After earning his PhD from Caltech in 1954, Gordon Moore took a position conducting basic research at the Applied Physics Laboratory at Johns Hopkins University. Fourteen years and two jobs later, he and his colleague Robert Noyce cofounded Intel Corp. Moore served as executive vice president of the company until 1975, when he took the helm. Under his leadership—as chief executive officer (1975 to 1987) and chairman of the board (1987 to 1997)—Intel grew from a Mountain View-based startup to a giant of Silicon Valley, worth more than $140 billion today.

Moore is widely known for "Moore's Law," his 1965 prediction that the number of transistors that can fit on a chip would double every year. Still relevant 50 years later, this principle pushed Moore and his company—and the tech industry as a whole—to produce continually more powerful and cheaper semiconductor chips.

Gordon Moore joined the Caltech Board of Trustees in 1983 and served as chair from 1993 to 2000. That same year, he and his wife established the Gordon and Betty Moore Foundation, an organization dedicated to creating positive outcomes for future generations in the San Francisco Bay Area and around the world.

Among numerous other honors, Gordon Moore is a member of the National Academy of Engineering, a fellow of the Institute of Electrical and Electronics Engineers, and a recipient of the National Medal of Technology and the Presidential Medal of Freedom. 

The Gordon and Betty Moore Graduate Fellowship Match is available for new gifts and pledges to endow graduate fellowships. For more information about the match and how to support graduate education at Caltech, please contact Jon Paparsenos, executive director of development, at (626) 395-3088 or jpapars@caltech.edu.

Exclude from News Hub: 
No
News Type: 
In Our Community

Clean Water For Nepal

On the steep, tea-covered hillsides of Ilam in eastern Nepal, where 25 percent of households live below the poverty level and electricity is scarce, clean running water is scarcer still. What comes out of the region's centralized distribution systems is unfiltered, untreated, and teeming with nitrates, viruses, and E. coli. Purifying it is the consumer's responsibility.

But wood and yak dung, the only available fuels for boiling water, are precious, and purification tablets impart an unpleasant chlorine taste. The result? During the rainy season, local hospitals overflow with typhoid and gastrointestinal cases, mostly involving children and tainted runoff.

That may change, thanks to a gravity flow and slow-sand filtration system designed by Caltech undergraduates. They represent EWB-Caltech, one of the newest chapters of Engineers Without Borders USA, a nongovernmental organization (NGO) whose mission is to design and implement sustainable engineering projects in underprivileged communities.

Founded in 2012 by Sarah Wright (BS '13, bioengineering), EWB-Caltech already has about 30 members. This summer, a half dozen of the chapter's members are traveling to Ilam, where they are staying with local villagers while helping to oversee and implement the system's construction. The hillside will be partly excavated and then reconstructed. Layers of rock, gravel, sand, polyethylene sheeting, and soil will soak up rainfall, filtering and purifying it as it trickles into underground water. Pipes tapping into the underground water will run downhill to a small communal enclosure made of poured concrete, providing a reliable supply of clean water for about 100 households, with another 200 indirectly affected.

The students will not be working alone, says their mentor, environmental engineering consultant Gordon Treweek (MS '71, PhD '75) who is partnering with Caltech engineering students for the first time. "All EWB projects are community-driven, with the local workforce providing much of the labor. And we've received tremendous logistical support, including interpreters, from the Namsaling Community Development Center, an NGO in Ilam that had previously worked with an EWB chapter from the University of Colorado, Boulder."

According to EWB requirements the Nepalese must contribute 5 percent of the project's budget. EWB-Caltech copresidents Jihoon Lee (a senior in bioengineering) and Nauman Javed (a senior in physics) acknowledge that successfully coming up with the remainder—over $20,000—involved nearly continuous fund-raising. "We've been applying for grants, soliciting private donations, partnering with companies, especially water-related and environmental corporations, and we held a benefit dinner in January that was largely attended by Caltech faculty and friends," says Lee.

Both a 10-day on-site assessment trip last summer and this summer's trip were covered by individual donations and grants. The assessment trip took Treweek, Javed, and fellow Caltech senior Webster Guan (chemical engineering) to Ilam to meet with the NGO; to survey the local community of about 100 families to ascertain their needs and willingness to assist in the construction and ongoing maintenance of the water tap stand; and to gather predesign data for planning construction and estimating costs.

"The support we have received from Caltech alumni directly and through their networks of contacts at Northrop Grumman and Boeing has been invaluable in helping to keep this project moving forward," Treweek says.

After the assessment trip, the students spent the 2014–15 school year preparing detailed engineering documents using computer-aided design techniques. In this, they were assisted by the water-resource engineering firms Carollo Engineers and Montgomery Watson Harza, whose pro bono involvement did not surprise Treweek. "Consulting engineering firms frequently donate resources for projects like this," he says. "It's socially responsible, and it gives them a chance to observe future engineers addressing the four traditional phases of engineering: planning, design, fund-raising, and construction."

With preventable infectious diseases a leading component of Ilam's one-in-three infant mortality rate, the project includes a public-education component. "Besides training the local villagers who will maintain our spring-water source protection system," says Javed, "we plan to visit local schools, demonstrate how the system works, teach a little germ theory."

But no amount of careful planning can guarantee success. Similar projects have failed due to engineering problems, misaligned long-term governance strategies, eleventh-hour reprioritizations by the community, even simple miscommunication. "We've drafted plenty of contingency plans," affirms Lee, "with great support from EWB-USA. Their stringent review procedures covered every engineering and social aspect of the project, and they've given us detailed feedback on our drawings, schedules, and rationales."

After the implementation phase—which ends just one week before classes resume back in Pasadena—EWB-Caltech will continue to monitor the site for five to six years. By then the current members will have moved on and a new group of student leaders will have taken over this project. But for now, they are spending their summer trying to build a better world, drop by drop.

Writer: 
Exclude from News Hub: 
No
News Type: 
In Our Community

New VP for Student Affairs Named

Joseph Shepherd (PhD '81), the C. L. "Kelly" Johnson Professor of Aeronautics and professor of mechanical engineering, is leaving his post as dean of graduate studies to succeed Anneila Sargent (MS '67, PhD '78), the Ira S. Bowen Professor of Astronomy, as vice president for student affairs. Shepherd's new role is effective September 15.

Sargent, who served the campus as the leader of student affairs the last eight years, announced in March that she was leaving the post to return to research and teaching full time. Shepherd, who joined the Caltech faculty in 1993, has served the last six years as the dean of graduate studies.

We recently sat down with Shepherd to talk about his past role and his new one, his strengths and goals, and his experience at Caltech.

 

Q: What does the vice president for student affairs do?

A: Student Affairs includes the offices of the undergraduate and graduate deans as well as obvious things like the registrar, undergraduate admissions, fellowships and study abroad, the career center, the health center, and the counseling center. It also includes things you might not think of—athletics; performing and visual arts, which includes the music programs, the theater program, the various arts programs, and all of the faculty and instructors that make these programs possible; and a whole group of organizations lumped under "auxiliaries."

The term "auxiliaries" is misleading, because they're central to student life. Housing and dining are the biggest parts, but there are services like the C-Store, the Red Door Café, the Caltech Store and Wired.

 

Q: What makes this role exciting for you?

A:  People speculate about what it is that makes Caltech a great school. A lot of folks say, "Well, it's because it's so small." But I think it's also because we work with people instead of creating some bureaucratic mechanism to solve problems. We say, "All right, what's the issue here? How can we resolve this?" instead of, "We need to create a rule. And then we need to create a group to enforce the rule." My approach is to ask, "What do we want the outcome to be?" In Student Affairs, you want the outcome to be something that supports the students, supports the faculty, and then you make sure that it's not going to adversely affect the Institute.

 

Q: Are there any changes coming, any initiatives you want to establish?

A: We need to think about how we build on the strengths we have and improve the things that we're weakest at. Before you make any changes to an organization, you need to understand those two things. There are a lot of parts to Student Affairs, so I need to understand the strong points of those organizations, and then get them to help me formulate what's important to do.

You always have to be careful of unintended consequences. As they say in chess, you want to think several moves deep. All right, suppose we do that. What will it mean for different parts of our population? Do we make this choice based on the data we have, or do we need more data? Will there be effects on people we haven't thought about? Maybe we need to go talk to those people.

When you have the authority to change things, you also have the responsibility to ask, "Are these the right changes?" Nothing happens in isolation. Anything you do is invariably going to wind up touching quite a few people.

 

Q: You've been dean of graduate studies since 2009. Did you consider taking a breather before jumping into this?

A: Well, much to my surprise, I found that being the dean of graduate studies was rewarding in many different ways. Sometimes you had to do some difficult things, but I actually liked being the dean. I was able, to some extent, to continue my research. I did some teaching—although last year I taught a major course all three terms, and I had my research group—and I was the dean of graduate studies. That taught me a lesson: a man's got to know his limitations.

So when I was asked if I would take this position, I did think about taking a break and not doing it. I enjoy my research and I enjoy teaching. I enjoy working with students, but I also enjoy trying to help the Institute as a whole. Here at Caltech, we pride ourselves on the notion that we have this very special environment. We have this small school, and we have dedicated professionals that work together with faculty to nurture that environment—having faculty who are invested in participating in the key administrative roles is essential.

When I was a graduate student here, my adviser was Brad Sturtevant [MS '56, PhD '60, and a lifelong faculty member thereafter]. Brad was the executive officer for aeronautics [1972-76]. He was in charge of the committee that built the Sherman Fairchild Library and he was on the faculty board. He emphasized to me that being involved in administration was just as valuable as all the other aspects of being a faculty member. He was a dedicated researcher, but he also felt strongly that you should be a good citizen. You should contribute.

 

Q: It seems like this is more than just a duty to you, though.

A: I'm looking forward to it. I'm also very conscious of the responsibility. I think it's going to be important for us all to think about how we maintain the excellence of the Institute and that we imagine how this place is going to evolve. As society evolves around us, we will naturally wind up changing. We need to do that in a thoughtful way so that we continue to be the special organization that we are.

At the end of the day, I'm counting on help from the faculty and staff. Caltech works because of the committed individuals within our organizations, the personal connections we form as we work together and the cooperation across the campus that these connections enable.  It's a collective enterprise.

I think administration is not something that's done to people. It's being responsible for making sure that folks have the right work environment, the right job assignments, and the right resources. It's making sure we're doing the right things with the finite resources we have. One of our former presidents said something that's always stuck with me: an administrator's goals are not about their own career so much as helping the careers of others. You need to think about how you're helping the people working for you, because they have goals and aspirations. That's where you take your satisfaction.

Home Page Title: 
New VP for Student Affairs
Writer: 
Exclude from News Hub: 
No
News Type: 
In Our Community
Exclude from Home Page: 
Thursday, September 24, 2015
Beckman Institute, Glanville Courtyard – Beckman Institute

3rd Annual Caltech Teaching Conference

Better Memory with Faster Lasers

DVDs and Blu-ray disks contain so-called phase-change materials that morph from one atomic state to another after being struck with pulses of laser light, with data "recorded" in those two atomic states. Using ultrafast laser pulses that speed up the data recording process, Caltech researchers adopted a novel technique, ultrafast electron crystallography (UEC), to visualize directly in four dimensions the changing atomic configurations of the materials undergoing the phase changes. In doing so, they discovered a previously unknown intermediate atomic state—one that may represent an unavoidable limit to data recording speeds.

By shedding light on the fundamental physical processes involved in data storage, the work may lead to better, faster computer memory systems with larger storage capacity. The research, done in the laboratory of Ahmed Zewail, Linus Pauling Professor of Chemistry and professor of physics, will be published in the July 28 print issue of the journal ACS Nano.

When the laser light interacts with a phase-change material, its atomic structure changes from an ordered crystalline arrangement to a more disordered, or amorphous, configuration. These two states represent 0s and 1s of digital data.

"Today, nanosecond lasers—lasers that pulse light at one-billionth of a second—are used to record information on DVDs and Blu-ray disks, by driving the material from one state to another," explains Giovanni Vanacore, a postdoctoral scholar and an author on the study. The speed with which data can be recorded is determined both by the speed of the laser—that is, by the duration of each "pulse" of light—and by how fast the material itself can shift from one state to the other.

Thus, with a nanosecond laser, "the fastest you can record information is one information unit, one 0 or 1, every nanosecond," says Jianbo Hu, a postdoctoral scholar and the first author of the paper. "To go even faster, people have started to use femtosecond lasers, which can potentially record one unit every one millionth of a billionth of a second. We wanted to know what actually happens to the material at this speed and if there is a limit to how fast you can go from one structural phase to another."

To study this, the researchers used their technique, ultrafast electron crystallography. The technique, a new development—different from Zewail's Nobel Prize–winning work in femtochemistry, the visual study of chemical processes occurring at femtosecond scales—allowed researchers to observe directly the transitioning atomic configuration of a prototypical phase-change material, germanium telluride (GeTe), when it is hit by a femtosecond laser pulse.

In UEC, a sample of crystalline GeTe is bombarded with a femtosecond laser pulse, followed by a pulse of electrons. The laser pulse causes the atomic structure to change from the crystalline to other structures, and then ultimately to the amorphous state. Then, when the electron pulse hits the sample, its electrons scatter in a pattern that provides a picture of the sample's atomic configuration as a function of the time.

With this technique, the researchers could see directly, for the first time, the structural shift in GeTe caused by the laser pulses. However, they also saw something more: a previously unknown intermediate phase that appears during the transition from the crystalline to the amorphous configuration. Because moving through the intermediate phase takes additional time, the researchers believe that it represents a physical limit to how quickly the overall transition can occur—and to how fast data can be recorded, regardless of the laser speeds used.

"Even if there is a laser faster than a femtosecond laser, there will be a limit as to how fast this transition can occur and information can be recorded, just because of the physics of these phase-change materials," Vanacore says. "It's something that cannot be solved technologically—it's fundamental."

Despite revealing such limits, the research could one day aid the development of better data storage for computers, the researchers say. Right now, computers generally store information in several ways, among them the well-known random-access memory (RAM) and read-only memory (ROM). RAM, which is used to run the programs on your computer, can record and rewrite information very quickly via an electrical current. However, the information is lost whenever the computer is powered down. ROM storage, including CDs and DVDs, uses phase-change materials and lasers to store information. Although ROM records and reads data more slowly, the information can be stored for decades.

Finding ways to speed up the recording process of phase-change materials and understanding the limits to this speed could lead to a new type of memory that harnesses the best of both worlds.

The researchers say that their next step will be to use UEC to study the transition of the amorphous atomic structure of GeTe back into the crystalline phase—comparable to the phenomenon that occurs when you erase and then rewrite a DVD.

Although these applications could mean exciting changes for future computer technologies, this work is also very important from a fundamental point of view, Zewail says.

"Understanding the fundamental behavior of materials transformation is what we are after, and these new techniques developed at Caltech have made it possible to visualize such behavior in both space and time," Zewail says.

The work is published in a paper titled "Transient Structures and Possible Limits of Data Recording in Phase-Change Materials." In addition to Hu, Vanacore, and Zewail, Xiangshui Miao and Zhe Yang are also coauthors on the paper. The work was supported by the National Science Foundation and the Air Force Office of Scientific Research and was carried out in Caltech's Center for Physical Biology, which is funded by the Gordon and Betty Moore Foundation.

Writer: 
Exclude from News Hub: 
No
News Type: 
Research News

New Dean of Graduate Studies Named

On July 1, 2015, Doug Rees, the Roscoe Gilkey Dickinson Professor of Chemistry, will begin serving as the new dean of graduate studies at Caltech.

"Doug's experience and concern with graduate education make him an ideal choice for dean of graduate studies. I am very pleased that he is willing to make this commitment to the Institute and its students," says Anneila Sargent, vice president for student affairs and the Ira S. Bowen Professor of Astronomy.

As the new dean, Rees will be the principal administrator and representative of Caltech's graduate education program, responsible for attending to concerns regarding the welfare of graduate students as well as for upholding the Institute's rules and policies.

"There are many groups essential to the effective operation of our graduate program that I want to get to know better, starting with the graduate students, the Graduate Office staff, and the option administrators and option reps," says Rees. "In my 26 years at Caltech, I've gained an appreciation for how the graduate programs in biochemistry and molecular biophysics and in chemistry operate, but the cultures in different options across campus can vary significantly, and I look forward to better understanding these distinctions."

Rees says that he is also very much looking forward to working directly with graduate students, staff, and faculty on behalf of the graduate program. Of particular interest during his tenure will be issues relating to the well-being and professional development of graduate students.

"I find research to be an adventure that, while exhilarating, is also challenging, frustrating, and even stressful; those aspects, however, are not incompatible with having a positive student experience and a supportive environment," Rees says. He adds that his priorities will be to raise fellowship support, increase the diversity of the graduate student body, and ensure that students have access to appropriate support services such as health care, counseling, and day care. "In addition, I also hope to be able to explore mechanisms to better prepare students for life after Caltech, including both academic and nonacademic career options," he says.

In his new post, Rees will take the place of C. L. "Kelly" Johnson Professor of Aeronautics and Mechanical Engineering Joseph Shepherd, who has served as the dean of graduate studies since 2009. "Joe leaves big shoes to fill and the campus owes him a huge debt of gratitude for all he has accomplished as dean of graduate studies. What I have learned from watching him in action over the past six years, and more recently as he has been helping me during this transition period, is that the most important quality for the dean is to care about the students—and I will definitely be working to follow his example," Rees says.

Rees received his undergraduate degree from Yale University in 1974 and his PhD from Harvard in 1980, becoming a professor at Caltech in 1989. An investigator with the Howard Hughes Medical Institute, Rees also served as the executive officer for chemistry from 2002 to 2006 and the executive officer for biochemistry and molecular biophysics from 2007 to 2015.

Writer: 
Exclude from News Hub: 
No
News Type: 
In Our Community

New Approach Holds Promise for Earlier, Easier Detection of Colorectal Cancer

Caltech chemists develop a technique that could one day lead to early detection of tumors

Chemists at Caltech have developed a new sensitive technique capable of detecting colorectal cancer in tissue samples—a method that could one day be used in clinical settings for the early diagnosis of colorectal cancer.

Colorectal cancer is the third most prevalent cancer worldwide and is estimated to cause about 700,000 deaths every year. Metastasis due to late detection is one of the major causes of mortality from this disease; therefore, a sensitive and early indicator could be a critical tool for physicians and patients.

A paper describing the new detection technique currently appears online in Chemistry & Biology and will be published in the July 23 issue of the journal's print edition. Caltech graduate student Ariel Furst (PhD '15) and her adviser, Jacqueline K. Barton, the Arthur and Marian Hanisch Memorial Professor of Chemistry, are the paper's authors.

"Currently, the average biopsy size required for a colorectal biopsy is about 300 milligrams," says Furst. "With our experimental setup, we require only about 500 micrograms of tissue, which could be taken with a syringe biopsy versus a punch biopsy. So it would be much less invasive." One microgram is one thousandth of a milligram.

The researchers zeroed in on the activity of a protein called DNMT1 as a possible indicator of a cancerous transformation. DNMT1 is a methyltransferase, an enzyme responsible for DNA methylation—the addition of a methyl group to one of DNA's bases. This essential and normal process is a genetic editing technique that primarily turns genes off but that has also recently been identified as an early indicator of cancer, especially the development of tumors, if the process goes awry.

When all is working well, DNMT1 maintains the normal methylation pattern set in the embryonic stages, copying that pattern from the parent DNA strand to the daughter strand. But sometimes DNMT1 goes haywire, and methylation goes into overdrive, causing what is called hypermethylation. Hypermethylation can lead to the repression of genes that typically do beneficial things, like suppress the growth of tumors or express proteins that repair damaged DNA, and that, in turn, can lead to cancer.

Building on previous work in Barton's group, Furst and Barton devised an electrochemical platform to measure the activity of DNMT1 in crude tissue samples—those that contain all of the material from a tissue, not just DNA or RNA, for example. Fundamentally, the design of this platform is based on the concept of DNA-mediated charge transport—the idea that DNA can behave like a wire, allowing electrons to flow through it and that the conductivity of that DNA wire is extremely sensitive to mistakes in the DNA itself. Barton earned the 2010 National Medal of Science for her work establishing this field of research and has demonstrated that it can be used not only to locate DNA mutations but also to detect the presence of proteins such as DNMT1 that bind to DNA.

In the present study, Furst and Barton started with two arrays of gold electrodes—one atop the other—embedded in Teflon blocks and separated by a thin spacer that formed a well for solution. They attached strands of DNA to the lower electrodes, then added the broken-down contents of a tissue sample to the solution well. After allowing time for any DNMT1 in the tissue sample to methylate the DNA, they added a restriction enzyme that severed the DNA if no methylation had occurred—i.e., if DNMT1 was inactive. When they applied a current to the lower electrodes, the samples with DNMT1 activity passed the current clear through to the upper electrodes, where the activity could be measured. 

"No methylation means cutting, which means the signal turns off," explains Furst. "If the DNMT1 is active, the signal remains on. So we call this a signal-on assay for methylation activity. But beyond on or off, it also allows us to measure the amount of activity." This assay for DNMT1 activity was first developed in Barton's group by Natalie Muren (PhD '13).

Using the new setup, the researchers measured DNMT1 activity in 10 pairs of human tissue samples, each composed of a colorectal tumor sample and an adjacent healthy tissue from the same patient. When they compared the samples within each pair, they consistently found significantly higher DNMT1 activity, hypermethylation, in the tumorous tissue. Notably, they found little correlation between the amount of DNMT1 in the samples and the presence of cancer—the correlation was with activity.

"The assay provides a reliable and sensitive measure of hypermethylation," says Barton, also the chair of the Division of Chemistry and Chemical Engineering.  "It looks like hypermethylation is good indicator of tumorigenesis, so this technique could provide a useful route to early detection of cancer when hypermethylation is involved."

Looking to the future, Barton's group hopes to use the same general approach in devising assays for other DNA-binding proteins and possibly using the sensitivity of their electrochemical devices to measure protein activities in single cells. Such a platform might even open up the possibility of inexpensive, portable tests that could be used in the home to catch colorectal cancer in its earliest, most treatable stages.

The work described in the paper, "DNA Electrochemistry shows DNMT1 Methyltransferase Hyperactivity in Colorectal Tumors," was supported by the National Institutes of Health. 

Writer: 
Kimm Fesenmaier
Home Page Title: 
A New Approach to Detecting Colorectal Cancer
Listing Title: 
A New Approach to Detecting Colorectal Cancer
Writer: 
Exclude from News Hub: 
No
Short Title: 
A New Approach to Detecting Colorectal Cancer
News Type: 
Research News

Caltech, JPL Team Up to Take On Big-Data Projects

Acknowledging not only the growing need among scientists and engineers for resources that can help them handle, explore, and analyze big data, but also the complementary strengths of Caltech's Center for Data-Driven Discovery (CD3) and JPL's Center for Data Science and Technology (CDST), the two centers have formally joined forces, creating the Joint Initiative on Data Science and Technology.

A kickoff event for the collaboration was held at the end of April at Caltech's Cahill Center for Astronomy and Astrophysics.

"This is a wonderful example of a deep cooperation between Caltech and JPL that we think will serve to strengthen connections between the campus and the lab," says George Djorgovski, professor of astronomy and director of CD3. "We believe the joint venture will enable and stimulate new projects and give both campus and JPL researchers a new competitive advantage."

Individually, each center strives to provide the intellectual infrastructure, including expertise and advanced computational tools, to help researchers and companies from around the world analyze and interpret the massive amounts of information they now collect using computer technologies, in order to make data-driven discoveries more efficient and timely.

"We've found a lot of synergy across disciplines and an opportunity to apply emerging capabilities in data science to more effectively capture, process, manage, integrate, and analyze data," says Daniel Crichton, manager of the CDST. " JPL's work in building observational systems can be applied to several disciplines from planetary science and Earth science to biological research."

The Caltech center is also interested in this kind of methodology transfer—the application of data tools and techniques developed for one field to another. The CD3 recently collaborated on one such project with Ralph Adolphs, Bren Professor of Psychology and Neuroscience and professor of biology at Caltech. They used tools based on machine learning that were originally developed to analyze data from astronomical sky surveys to process neurobiological data from a study of autism.

"We're getting some promising results," says Djorgovski. "We think this kind of work will help researchers not only publish important papers but also create tools to be used across disciplines. They will be able to say, 'We've got these powerful new tools for knowledge discovery in large and complex data sets. With a combination of big data and novel methodologies, we can do things that we never could before.'"

Both the CD3 and the CDST began operations last fall. The Joint Initiative already has a few projects under way in the areas of Earth science, cancer research, health care informatics, and data visualization.

"Working together, we believe we are strengthening both of our centers," says Djorgovski. "The hope is that we can accumulate experience and solutions and that we will see more and more ways in which we can reuse them to help people make new discoveries. We really do feel like we're one big family, and we are trying to help each other however we can."

Writer: 
Kimm Fesenmaier
Writer: 
Exclude from News Hub: 
No
News Type: 
In Our Community

Pages