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Diving Deep for Alternative Energy
Cigarette Warnings with Images: Better at Conveying Risks of Smoking
Illustrating Impact of Drone Usage in Areas of Conflict
Diving Deep for Alternative Energy
When Alison Sweeney, an assistant professor in Penn’s School of Arts & Sciences’ department of physics & astronomy, went scuba diving in Palau this summer, she wasn’t on vacation. A tropical paradise on the surface, the coral reefs under the tiny island nation’s azure waves are actually a laboratory unlike anywhere else on the planet. The seemingly placid environment features some truly extreme conditions—an evolutionary crucible that has produced creatures with traits that rival the best of human ingenuity. Dr. Sweeney’s job is to understand how they got that way and why.
Though Dr. Sweeney’s departmental colleagues include condensed-matter physicists and theoretical topologists, she is a biologist by training. She came to be in this interdisciplinary nexus because the biological structures she studies are exquisite manipulators of the electromagnetic spectrum. Many sea-creatures have evolved light-reflecting structures that are used to hide from predators, confuse prey, attract mates, and in the case of the giant clams that live in Palau, grow their own food.
The clams have a symbiotic relationship with algae, which grow in pillars inside their flesh. As the algae reproduce, they push each other off of the bottom of the pillars and into the clam’s stomach. “They are essentially farming the algae for nutrients,” Dr. Sweeney said.
As part of the Evolution Cluster, which brings together scholars from departments across Penn Arts & Sciences to study different facets of this core scientific concept, Dr. Sweeney’s research involves understanding how the clams came to be able to perform this trick. Though Palau’s landscape is lush, surviving there is harder than it seems.
“Sunlight at the equator is so intense that most plants can’t make use of it without being damaged,” Dr. Sweeney said. “But we’ve found that the clams have a way of scattering the light into wavelengths that the algae can most efficiently absorb.”
The evolutionary solution that the giant clam has stumbled upon is a structure known as an iridocyte. Roughly spherical cells packed with reflective proteins, a layer of these iridocytes is spread on top of the pillars, giving the clams their iridescent sheen when seen from above. Below, the iridocytes spread that blue and red light to the sides of the algae pillars. Because the plants are green-brown, and thus reflect more light of those wavelengths, the clams can grow them most efficiently by sparing them from all but the most valuable photons.
Evolution has so precisely tailored giant clams to their environment that their algae-farming efficiency outstrips anything humans have achieved in the quest to use the single-celled plants as a biofuel. State-of-the-art bioreactors can quickly fill tubes or pools with the neon green organisms, but that is only half the battle. Algae on the surface of these reactors block light from reaching their brethren on the inside; to keep them all alive, the reactors must be constantly stirred, losing whatever energy gains harvesting the algae would produce.
With this challenge in mind, Dr. Sweeney is collaborating with Penn’s School of Engineering & Applied Science’s Shu Yang on a National Science Foundation grant that aims to replicate the light-scattering abilities of iridocytes with lab-made materials. The funding will support a Palauan graduate student, who will travel to Penn to work with Drs. Sweeney and Yang, as well as several local interns.
Cigarette Warnings with Images: Better at Conveying Risks of Smoking
A study using a real-world approach to evaluate graphic warning labels on cigarette packs has found that the emotionally engaging images are more successful than simple text warnings at educating smokers about the risks of smoking. In research released in the journal PLOS One, the first study of day-to-day exposure to the pictorial warnings proposed by the Food and Drug Administration in 2011 showed that smokers using their own brand of cigarettes for four weeks with the pictorial warnings were better able to recall the warnings and name the health risks associated with the habit than smokers who were merely exposed to textual information. The graphic warning labels also were found to be more credible.
“This study shows that pictorial warnings do a better job of educating smokers than text alone,” said Daniel Romer, research director of Penn’s Annenberg Public Policy Center (APPC). He co-directed the study in a joint project with researchers at the Ohio State University. “Concerns raised by the courts that pictorial warnings that illustrate the risks of smoking are uninformative overlook the potential of these warnings to help smokers confront the risks of their habit.”
In a suit brought by tobacco companies, the US Court of Appeals in Washington ruled in 2012 that the FDA-proposed graphic warning labels “do not convey any warning information at all” and were “unabashed attempts to evoke emotion (and perhaps embarrassment) and browbeat consumers into quitting.”
The PLOS One study analyzed data from 244 adults who smoked between five and 40 cigarettes a day. The smokers, from both Philadelphia and Columbus, Ohio, were given their own brand of cigarettes to smoke for four weeks with either the pictorial labels proposed by the FDA on the front and back of the packs or the text mandated by Congress in the Family Tobacco Act of 2009 on the side of the pack, where current warnings reside. Those text warnings were presented more prominently and included more information about the risks of smoking than the current warnings, which research has shown are largely ignored. The pictorial warnings were seen as more believable than the text-only warnings and were more likely to change smokers’ feelings about their habit.
Research in other countries such as Canada, where color pictorial warnings were first introduced in 2001, suggests that they encourage smokers to quit. However, this research does not permit clear conclusions because the warnings are almost always introduced along with other changes in the market, such as price increases.
“The value of a clinical trial, such as the one that we conducted, is that it enables us to isolate the effects of exposure to pictorial warnings in direct comparison with text-only warnings,” Dr. Romer noted.
Co-authors of the study were Abigail T. Evans and Ellen Peters of the Ohio State University; Andrew Strasser of Penn’s Perelman School of Medicine; Lydia F. Emery of Northwestern University; and Kaitlin M. Sheerin of the University of Missouri.
Illustrating Impact of Drone Usage in Areas of Conflict
The use of drones has had significant consequences for how governments conduct counter-terrorism operations. But technological limitations mean they are less likely to effect wars between countries, according to a new paper co-authored by Michael C. Horowitz, a political scientist in Penn’s School of Arts & Sciences. In “The Consequences of Drone Proliferation: Separating Fact from Fiction,” Dr. Horowitz, associate director of Penn’s Perry World House, argues that drones have the potential to enhance security in disputed border regions because they easily allow states to monitor what’s happening.
The article’s co-authors, which include Sarah E. Kreps from Cornell University and Matthew Fuhrmann from Texas A & M University, examine the effects of drones in counterterrorism, interstate conflict, crisis onset and deterrence, coercive diplomacy, domestic control and repression. They underscore ways in which the analysis challenges emerging views on drone proliferation, and they identify national security implications for the US.
The article explains that there are two polarizing schools of thought regarding drones. Pessimists draw attention to all of the ways drones are undesirable, while others believe that unmanned aerial vehicles are harmless because of their operational limitations, which include a low flying speed and vulnerability to air defense systems. The authors maintain that both of these views are incomplete and that there are many other factors to consider.
“Those who argue that drones are transformative overlook important operational limits of the technology,” Dr. Horowitz said. “The more dismissive view, by contrast, fails to fully appreciate how removing pilots from aircraft changes the decision-making calculus of using drones versus manned alternatives.”
With a comprehensive assessment of the consequences of current-generation drone proliferation, including how both perspectives are misguided, Drs. Horowitz, Kreps and Fuhrmann say what’s missing from the current debate is a realistic understanding of what today’s drones can and cannot do.
“Accurately capturing the capabilities of current generation drones is critical to understanding how drones may or may not change military affairs or world politics more generally,” Dr. Horowitz said.
The article explores the history of unmanned aerial vehicles dating back to the mid-1800s and ongoing trends. For example, during the Xinjiang protests in 2014, China sent out surveillance drones to monitor the situation. But, as the use of armed drones continue to spread, it will mean dictators can do more than just surveillance. With armed drones, there is a possibility for repression.
“Drone proliferation carries potential significant consequences for counterterrorism operations and domestic control in authoritarian regimes,” Dr. Horowitz wrote. “Drones lower the costs of using force by eliminating the risk that pilots will be killed, making some states, especially democracies, more likely to carry out targeted attacks against suspected militants.”
The co-authors conclude that, if used to monitor disputed territories and borders, drones have the potential to reduce uncertainty about an adversary’s behavior, which could promote peace if the enemy’s intentions are benign. “Drones are neither a game changer across every dimension of international security, nor simply a redundant military technology with little significance for international security. The consequences could change dramatically as technical advancements occur over time.”
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