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Time Stands Still for Rotunda Clock During Renovations

Fri, 2015-07-31 14:52
Matt Kelly

The Rotunda clock was the official timepiece of the University of Virginia — a black dial face with gilded numbers that measured the time passing in the Academical Village. And after measuring its service in years, the clock is getting a facelift and an update.

University founder Thomas Jefferson commissioned Boston clockmaker Simon Willard to construct the original Rotunda clock, and the two men exchanged letters outlining the specifications of the clock. Willard and Jefferson’s clock was 60 inches across the dial face, and the bezel, or the ring around the outside of the clock, was 10 inches wide.

This clock dominated the pediment of the south portico, facing the Lawn and the Academical Village. There was no clock on the north side of the original Rotunda, but when the Annex was built, there was an exterior clock on its north end.

“The inner workings were Willard’s forte,” said Christian Kochuba, 20, of Colonial Heights, a rising fourth-year architecture student who is the Edsall fellow working in the Office of the Architect for the University this summer.

The Willard clock was destroyed in the 1895 fire that heavily damaged the Rotunda, and when New York architect Stanford White, of the firm McKim, Mead and White, re-envisioned the Rotunda, he commissioned a slightly smaller model from E. Howard and Co., clockmakers of Boston. The Howard clock had a 55-inch dial face and 5 1/2 inch  bezel. White ordered two clocks, one for the south portico and a matching one for the north portico that White added to the remodeled Rotunda.

The conservators who are restoring the Howard clock believe the colors appear to be similar to the Willard timepiece.

“With the Jefferson clock it is hard to determine because all we have are black and white photographs,” Kochuba said. “Historically, tower clocks had a black dial plate with gilded numbers and hands. The bezel was darker than white, so it may have been gilded.”

The clock’s numbers were eventually painted white at some point, though Kochuba said that it appears that the dial plate was painted black many times and the black paint had encroached on the numbers. At some point the minute stops were painted over. In the mid 20th century, the numerals were even painted with a luminous paint so the clock could be read at night.

The original Howard clock had pierced, ornate hands, which were replaced at some point with less elaborate wooden hands, possibly made from mahogany, probably some time in the late 1960s.

“As we were going through the records, 1969 was the earliest photo we found with the current hands,” Kochuba said.

Initially, the two Rotunda clocks were controlled by a master clock at Rouss Hall, which housed the physics lab at that time. The clocks, in addition to class bells, were linked throughout every academic building by a single wire circling the Academical Village.

“This system was prone to failure,” said Mark Kutney, an architectural conservator in the Office of the Architect for the University.

Similar to a string of Christmas lights, if one bell malfunctioned, the entire system failed. One short circuit or break in the wire would cause the clocks to gain time rapidly or stop completely.

In 1922-23, Mr. Hoxton and Mr. Weed, two University physics professors, revamped the faulty clock and bell system. They rebuilt the Rotunda clocks to be regulated by their own weights and pendulums while being electrically set by the Rouss Hall clock. Additionally, they replaced the class bells to be much sturdier, and inserted a more reliable wiring system.

The Rotunda timepieces were electrified again on Oct. 23, 1948, by Town Clock Service Co. of Springfield, Ohio, according to notations made on the walls near the mechanisms.  

“The names of the men who did the work were written on the wall of the clockhouse,” Kochuba said. “And they noted on the wall every year they came back and did annual service. They wrote on the wall every year and it stopped in 1959.”

Kutney said the work on restoring the clocks will continue through the fall, including making new, gilded aluminum clock hands  based on the original Howard hands.

An excerpt from an E. Howard clock company catalog from the early 20th century describing the preparation of a tower clock dial states, “experience has demonstrated that dials having a dead black ground, with gilt figures and hands, are legible at a greater distance than any other combination of colors.”  

“Through forensic paint analysis we are able to verify that the first appearance of the current dial was in fact gilded numerals on a black background,” Kutney said. The equipment used to conduct the analysis was made possible through a grant from the Jefferson Trust Foundation.

The plan now is to replace the clock works with modern, quartz driven mechanisms that have a maximum four-minute drift per year, and a GPS option with zero-minute drift. The clocks will reset themselves automatically after power outages and for daylight savings.

On the clock face, the conservators are looking at 100 years of painting over.

“There are several possible options for presenting a restored dial. The most tedious option would be to uncover the original gilded elements,” Kutney said. “This would be a very slow and technically challenging process, very much like restoring a painting. We would definitely argue for this option if we were working on the Willard dial. Another option would be to simply scrape, sand and then paint a new set of numerals and stops over what’s left of the old, just like painting one’s house. We’re even considering painting a new face on a new one-fourth inch dial plate and installing the new dial over the old.  This approach would allow the highest level of preservation, since we would not disturb the original Howard dial in any way.”

Kutney said the University is working with clockmaker Bob Desrochers of Lititz, Pennsylvania, who restored the Cocke Hall tower clock to its original operating condition and restored the bronze bell and carriage at the chapel.

Professor’s Wearable Tech Study Tracks Impact of Tysons Corner Redevelopment

Fri, 2015-07-31 11:32
Caroline Newman

Just outside Washington, D.C., Tysons Corner is undergoing one of the most ambitious re-urbanization projects in the world. Planners and policymakers hope to transform the 4.3-mile suburban sprawl of shopping malls, offices and snarled roadways into a cohesive, well-organized and green urban space, friendly to pedestrians and motorists alike.

Improvements will layer residential and commercial buildings with green and pedestrian spaces – a strategy urban planners term densification. Benefits can include improved access to jobs, reduced automobile dependency and additional housing – critical in an expensive region like Northern Virginia.

“Tysons Corner is on the forefront of transforming suburban places into more urban places and all that entails,” said University of Virginia School of Architecture assistant professor Andrew Mondschein. “For city and urban planners, it is exciting, because if we densify suburbs we could reduce driving and emissions, provide more housing and make transit, walking and biking easier and more pleasant – hopefully improving public and environmental health. The Tysons Corner project embodies all of these wonderful goals.”

But will it actually work? Mondschein plans to find the answers — in impressive detail.

 This month, he will send a team of U.Va. students to Tysons Corner, which he calls “an archetypal American edge city,” equipped with a plethora of wearable cameras and sensors, as well as smartphone monitoring apps. This team will monitor temperature, light levels, green cover, noise pollution and carbon monoxide emissions in every corner of the development, continuing tactics used by a team Mondschein sent last summer at the outset of the project.

The resulting data paints a microscopic, on-the-ground picture of the average person’s experience at Tysons Corner, using objective fact. Coupled with public opinion surveys Mondschein is conducting, it will provide a ground-level view of exactly how improvements affect pedestrians’ experiences.

“I want to see how attitudes, the environment and behavior are changing in concert with each other or at different rates and to see the magnitude of the changes,” he said. “I want to show how what we plan actually leads to what we want to see.”

So far, the data has validated complaints voiced in the opinion surveys Mondschein has conducted.

“Right now, objectively, [Tysons] is a terrible place to be a pedestrian,” Mondschein said, citing factors like unusually high temperatures and oppressive glare near Leesburg Pike and the new Silver Line Metro station and greenspace shunted off to less trafficked areas.

Such granular data captures information that large organizations like the Virginia Department of Transportation would not otherwise collect, simply because of competing priorities and resource constraints.

Mondschein believes that other communities could use low-cost and user-friendly wearable devices to crowdsource research and capture similar data that might otherwise be lost. These devices include smartphones, cameras such as GoPros, and purpose-built compact sensors that can be easily worn or carried.  In addition to capturing stills and videos for image processing, the devices can monitor temperature, light, and noise levels, as well as other environmental factors such as air quality.

“With devices like these, communities could self-organize and self-initiate studies that can show what they need in an objective manner, with hard data,” Mondschein said. “That can be arguably more persuasive when speaking to policymakers, fundraisers and politicians.”

That democratization of the planning process could give local residents a sense of ownership and pride in their public spaces and empower them to seek the kind of transformation officials hope to achieve at Tysons Corner.

“Urbanization and densification could play an important role in solving some of the problems we face as an auto-based society,” Mondschein said. “It’s not just about sustainability, but also providing better, more affordable access for people who cannot afford cars and giving people places to walk, potentially leading to better health.”

The Tysons Corner redevelopment is expected to host up to 100,000 residents and 200,000 jobs by 2050. Mondschein hopes to monitor the development through its many stages, both through his own research and by eventually crowdsourcing his methods to provide the local community with tools to continue collecting data as Tysons transforms.

Stars In Our Galaxy Move Far From Home

Thu, 2015-07-30 16:38
Matt Kelly

Right now, in a galaxy right here, stars are changing their orbits.

Scientists from the University of Virginia and other schools, working with the Sloan Digital Sky Survey, have created a new map of the Milky Way and determined that 30 percent of stars have dramatically changed their orbits. This discovery of significant stellar migration brings a new understanding of how stars are formed and travel throughout the galaxy.

To build a map of the Milky Way, the scientists used the SDSS Apache Point Observatory Galactic Evolution Explorer (APOGEE) spectrograph to observe 140,000 stars during a three-year campaign. This project was led by astronomers from the University of Virginia, New Mexico State and the Institute for Advanced Study in Princeton, New Jersey, and included a collaboration of dozens of astronomers from around the world.

“The migration process we describe took place over the life of the disk of the Milky Way, so over the last 10 billion years,” said Steve Majewski, a professor of astronomy at U.Va. “We found the evidence for the process within our survey data taken from 2011 to 2014 and continuing.”

Future studies by astronomers using data from SDSS promise even more new discoveries.

"These latest results take advantage of only a small fraction of the available APOGEE data," said Majewski, the principal investigator of APOGEE. "Once we unlock the full information content of APOGEE, we will understand the chemistry and shape of our galaxy much more clearly."

The APOGEE survey is made possible by a unique, state-of-the-art, multi-object infrared spectrograph designed and assembled in the labs of the U.Va. Department of Astronomy, Majewski said. This continues to pay dividends in helping astronomers understand the nature of the stellar populations in the galaxy. 

“The U.Va. Department of Astronomy is currently in the process of building a second APOGEE spectrograph to be used on a telescope in Chile to explore the parts of the Galaxy only accessible from the Southern Hemisphere,” Majewski said.  “These new results from the first instrument operating from New Mexico only whet our appetites for the new discoveries that await APOGEE’s probe of the Southern Milky Way."

Majewski said the second instrument will be commissioned in Chile next year.

 “The instrument team from the Department of Astronomy, led by faculty members John Wilson and Michael Skrutskie, should be proud of the numerous discoveries about the Milky Way and its constituent stars and planets being made in such a short time since we commissioned the APOGEE instrument on the Sloan Telescope in New Mexico,” Mejewski said.

"In our modern world, many people move far away from their birthplaces, sometimes halfway around the world," said Michael Hayden of New Mexico State University, the lead author of the new study. "Now we're finding the same is true of stars in our galaxy — about 30 percent of the stars in our galaxy have traveled a long way from the orbits in which they were born."

The key to creating and interpreting this map is measuring the elements in the atmosphere of each star. "From the chemical composition of a star, we can learn its ancestry and life history," Hayden said.

The chemical information comes from spectra, which are detailed measurements of how much light the star gives off at different wavelengths. Spectra show prominent lines that correspond to elements and molecules present. Reading the spectral lines of a star can tell astronomers what the star is made of.

"Stellar spectra show us that the chemical makeup of our galaxy is constantly changing," said Jon Holtzman, an astronomer at NMSU who was involved in the study. "Stars create heavier elements in their cores, and when the stars die, those heavier elements go back into the gas from which the next stars form."

As a result of this process, called chemical enrichment, each generation of stars has a higher percentage of heavier elements than the previous generation did. In some regions of the galaxy, star formation has proceeded more vigorously than elsewhere — and in these more vigorous regions, more generations of stars have formed. Thus, the average amount of heavier elements in stars varies across different parts of the galaxy.  Astronomers can use the amount of heavy elements in a star to determine in which part of the galaxy the star was born.

Hayden and colleagues used APOGEE data to map the relative amounts of 15 separate elements, including carbon, silicon and iron, for stars all over the galaxy. What they found surprised them — up to 30 percent of stars had compositions indicating that they were formed in parts of the galaxy far from their current positions.

"While on average the stars in the outer disk of the Milky Way have less heavy element enrichment, there is a fraction of stars in the outer disk that have heavier element abundances that are more typical of stars in the inner disk," said Jo Bovy of the Institute for Advanced Study and the University of Toronto, another key member of the research team.

When the team looked at the pattern of element abundances in detail, they found that much of the data could be explained by a model in which stars migrate into new orbits around the galactic center, moving nearer or farther with time. These random in-and-out motions are referred to as "migration," and are likely caused by irregularities in the galactic disk, such as the Milky Way's famous spiral arms. Evidence of stellar migration had previously been seen in stars near the sun, but the new study is the first clear evidence that migration occurs for stars throughout the galaxy.

Strange Circular DNA May Offer New Way to Detect Cancers

Wed, 2015-07-29 16:36
Josh Barney

Strange rings of DNA that exist outside chromosomes are distinct to the cell types that mistakenly produced them, researchers have discovered. The finding raises the tantalizing possibility that the rings could be used as an indicator of different types of cancer. 

MicroDNAs, as the new class of DNA has been named, were first discovered by a team of researchers at the University of Virginia School of Medicine. Following up on that discovery, the researchers – led by Dr. Anindya Dutta, chairman of the Department of Biochemistry and Molecular Genetics – have established that microDNAs are lineage-specific: Different cell types, such as prostate cancer cells or ovarian cancer cells, produce microDNAs that are unique to that cell type. That makes them a potential biomarker with the ability to reveal the biological processes, and mistakes, behind their production.

A Product of Errors

MicroDNAs are too small to encode for any genes but have been found to exist in all cell types of the human body due to errors during the DNA copying process. MicroDNAs are produced from the active parts of the genome and from the part of the genome that is most susceptible to “stickiness,” and therefore leads to damage, during the RNA transcription process. 

Certain sections of DNA, called the GC base pairs, are held tightly together. While being transcribed on these more compact and stickier sections of DNA, RNA can adhere and form loops, which are then removed by a repair pathway, forming microDNAs. 

Hope for a Cancer Test

A defect in the pathway that corrects DNA damage, the mismatch repair pathway, highly increases the susceptibility to colon and other cancers in humans. Cancer cells, which have undergone genetic mutations and errors, have high levels of microDNAs, allowing their presence in large number to be exploited as a biomarker for cancer.

 “One of our favorite hopes is that sometime in the future, we will find that there are microDNAs circulating in the blood, and by seeing from which portion of the genome the microDNAs are coming, we can say ‘Ah ha, these are coming from say ovarian cancer cells, and these are much higher in number than they should be, so perhaps the person has a very early stage ovarian cancer, that can then be treated very effectively by surgery,’” Dutta said. 

Findings Published Online

The discovery has been described in a paper published online by the scientific journal Cell Reports. It was authored by Laura Dillon, Pankaj Kumar, Shunichi Takeda (University of Kyoto, Japan), Yves Pommier (National Cancer Institute, Bethesda, Md.), Jack Griffith (University of North Carolina at Chapel Hill), Yuh-Hwa Wang and Dutta. The work was supported by fellowships to Dillon (Ovarian Cancer Research Fund) and Kumar (Department of Defense, Prostate Cancer Research Program) and by National Institutes of Health grants.

Forbes Names U.Va. Nation’s Second Highest-Ranking Public University

Wed, 2015-07-29 16:21
Caroline Newman

Forbes has again named the University of Virginia the nation’s No. 2 public university in its annual ranking of America’s Top Colleges, released Wednesday.

The University ranked No. 36 overall among all public and private institutions, up four spots from its No. 40 ranking last year. U.Va. ranked  No. 20 among research universities and No. 5 among universities in the South. In total, 650 institutions were considered.

When compiling the rankings, Forbes considered five main categories:

  • Post-graduate success, based on alumni salary and appearances on various leadership rankings
  • Student satisfaction, based on transfer rates, online faculty ratings and social media surveys
  • Student debt, based on average federal student loan debt, student loan default rates and percentage of students taking federal loans
  • Graduation rate, based on how many students complete their degree in four years
  • Academic success, based on the number of prestigious scholarships and fellowships won by students

The rankings, generated in partnership with the Center for College Affordability and Productivity, were intended to prioritize student and alumni outcomes and return-on-investment.

Pomona College, followed by Williams College and Stanford University, earned the top overall ranking. Excluding military academies, the University of California Berkeley earned the top spot among public institutions, followed by U.Va. and the College of William and Mary.