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Dutt and Jude Grosser from the UF Citrus Research and Education Center are developing genetically engineered limes containing some similar genetic factors that are expressed in grape skin and blood orange pulp. These modified Mexican limes have a protein that induces anthocyanin biosynthesis, the process that creates the "red" in red wine, and causes the limes to develop a range of colors in the pulp from dark purple to fuchsia. "Anthocyanins are beneficial bioflavonoids that have numerous roles in human well-being," Dutt explained. "Numerous pharmacological studies have implicated their intake to the prevention of a number of human health issues, such as obesity and diabetes." Anthocyanins also naturally occur in a variety of oranges called blood oranges, which has a red to maroon colored flesh and, some say, a better taste than Florida's "blond" oranges. But blood oranges need cold temperatures to develop their trademark vibrant color. They grow and color well in the cooler climates of Spain and Italy, but do not exhibit the characteristic blood red color when grown in the subtropical climate of the Florida citrus belt. These new limes were developed using genes isolated from the red grape "Ruby Seedless" and the Blood Orange "Moro." Research on the utilization of these genes was conducted initially to develop a more consumer-friendly, alternative, plant-derived, system. They are the first step toward Florida farmers producing blood oranges and, possibly, a new grapefruit cultivar. In addition to changing the color of the fruit, the introduction of anthocyanins also change the color of leaves stems and flowers, and could lead to the creation of ornamental citrus plants. "Novel fruit, leaf, and flower colors could be produced by regulating anthocyanin biosynthesis," Dutt said. "Flower color ranged from light pink to fuchsia." Dutt and Grosser's study is being published in the January edition of the Journal of the American Society for Horticultural Science.

The scientists have found what researchers call a "transcription factor," called ROC40. Bala Rathinasabapathi, a UF/IFAS professor of horticultural sciences, likened a transcription factor's role in controlling the expression of many genes inside the algae cells to a policeman controlling a large crowd. To draw lipids out of algae, scientists must starve the algae of nitrogen. Among the hundreds of proteins modulated by nitrogen starvation, the synthesis of ROC40 was the most induced when the cells made the most oil. The high induction of that protein suggested to scientists that it could be playing an important biological role, said Elton Gonçalves, a former UF/IFAS doctoral student in the plant molecular and cellular biology program. In fact, the team's research showed that ROC40 helps control lipid production when the algal cells were starved of nitrogen. "Our discovery about the ROC40 protein suggests that it may be increasing the expression of genes involved in the synthesis of oil in microalgae," Rathinasabapathi said. "Such information is of great importance for the development of superior strains of algae for biofuel production," Gonçalves said. "We conducted this research due to the great socioeconomic importance of developing renewable sources of fuels as alternatives for petroleum-based fuels for future generations. In order to advance the production of algal biofuels into a large-scale, competitive scenario, it is fundamental that the biological processes in these organisms are well understood." Rathinasabapathi said this information is valuable for the future for engineering algae so it overproduces oil without starving the algae of nitrogen. Lipids from microalgae provide an excellent renewable source for biofuels. The algae grow quickly, tolerate extreme weather conditions and do not pose the same issues as biofuel crops that are grown both for fuel and food. The rub was if algae are deprived of nitrogen, the cells become stressed and begin to produce lipids, but their growth rate slows. And if alga is going to become a commercially viable fuel source, scientists must ensure that not only can it produce as much oil as possible, but also that it can grow as fast as possible. Rathinasabapathi and Gonçalves co-authored the study, which has been accepted for publication in The Plant Journal. More information: Elton C. Goncalves et al. Nitrogen starvation-induced triacylglycerol accumulation in the green algae: Evidence for a role for ROC40, a transcription factor involved in circadian rhythm, The Plant Journal (2016). DOI: 10.1111/tpj.13144

News Article
Site: phys.org

The acacia ants she studies, Crematogaster mimosae, use their fearsome bite to defend their host trees against large animals such as elephants and giraffes that eat the trees' leaves. Even elephants' thick skin can't protect them from the ants, which bite them inside their trunks. "They really seem to have a knack for finding your soft tissue," Rudolph said. "It's a nasty business." Ants are also aggressive toward each other, fighting to the death over their tree territories. While the consequences for losing colonies are stark—loss of territory or colony death—Rudolph and UF postdoctoral research associate Jay McEntee wanted to understand the costs to the winners. After a fight, victorious colonies have to defend their newly gained territory with a workforce heavily depleted by fighting. In a new study funded in part by a National Geographic Society/Waitt Fund Grant and published in Behavioral Ecology, Rudolph and McEntee found that victorious colonies might offset this challenge by recruiting members of the losing colonies to help. In experiments based at Mpala Research Centre in Kenya, researchers instigated ant wars by tying unrelated colonies' trees together, counting casualties in tarps placed below. By simulating the browsing of a large mammal, they discovered that victorious colonies are less able to defend their host trees after fights. After analyzing the DNA of nearly 800 ants, they discovered that fighting changes the genetic make-up of victorious colonies. Long viewed as fortresses of cooperating sisters, where relatives of the queen work for her benefit, Rudolph's work demonstrates that non-relatives can become part of the colony—and potentially defend its residents and territory. Researchers were further surprised to find that, in some cases, fatal fights with thousands of casualties do not produce a distinct winner. Instead, colonies cease fighting and fuse together, with the queen of each colony still alive. "Colonies are battling so aggressively that many individuals die, but then they are able to just stop fighting and form a lasting truce," Rudolph said. "It's pretty remarkable." How they know to stop fighting remains is a mystery, showing the need for research on recognition systems. One possibility, Rudolph says, is that fighting changes the odors ants use to distinguish nestmates from potential invaders. "If so, the updated or blended cues shared by prior foes may help end aggressive responses," Rudolph said. Sorting out these processes could contribute to our understanding of an intriguing aspect of physical conflict - that animal combatants become more similar biologically through combat. That can be true for humans, too: A 2013 study showed that the skin bacteria communities of competing roller derby teams converge during bouts, not unlike Rudolph's findings in ants. "Physical combat not only yields biological winners and losers," Rudolph said. "It can alter the identity of its combatants."

News Article | April 20, 2016
Site: www.fastcompany.com

This spring, Caleb Kinsella was one of the thousands of high school seniors around the country anxiously waiting to find out if he got into the college he wanted. At 6 p.m. one day, his top school, the University of Florida (UF), would update its website with every applicant’s acceptance status all at once. UF is a great school, in the top 50 in the country according to U.S. News and World Report, and Kinsella (who, full disclosure, is my nephew) wasn’t sure he would make the cut with his just-okay grades and test scores. So he was thrilled and a little surprised when he found out that he’d gotten in. Except, the more he looked, the more it seemed like something wasn't quite right. "It kind of fooled me at first," Kinsella told me. "It said, ‘Congratulations, you’ve been admitted to the University of Florida.’ But shortly after, I discovered it was actually the ‘Path to Campus Enrollment.’ Is that what it’s called? The PaCE program." Kinsella had been accepted to a year-old program at UF that lets students who don’t quite make the cut for traditional admission take their first two years of classes online or at a community college for a 25% discount in tuition. They can start taking classes on UF’s campus only after they earn 60 credits, and start as juniors. This combination of online and offline education is new, but gaining in popularity. Many institutions around the country, including the University of Colorado and , offer so-called hybrid degrees for bachelor's or master's students in many fields of study. This is all part of an expansion in online education that’s been progressing fitfully for most of this decade, an experiment involving millions of young people whose results are far from certain. While U.S. News and World Report ranks more than 200 online bachelor's programs, fewer than half of them report their graduation rates. Of the 69 programs that did, only 16 graduate more than half of their students. And those who did manage to complete their courses took a long time: Only 35% of programs had students who graduated within six years. Online education began to capture the educational world’s imagination in a serious way in 2012, which the New York Times called "the year of the MOOC," or massive open online class. Startups like Coursera, Udacity, and EdX promised to permanently change the way young people learned. In a TED talk from that year, Coursera cofounder Daphne Koller spoke about MOOC’s ability to solve problems as diverse as the legacy of apartheid in South Africa and the burden of student debt in America. Coursera’s goal, she said, was "to take the best courses from the best universities, and provide them to everyone around the world, for free." Ben Maddox, New York University's chief instructional technology officer and one of its primary online education pioneers, calls this time "MOOC fever." It was "a time of heightened awareness and expectations," he told me, which "caused us to think about instruction in new and different ways. It was energizing." One of the earliest MOOC providers was Udacity, founded by former Google VP and professor Sebastian Thrun. He started the company in early 2012 after being involved in an online education pilot program at Stanford. "MOOCs didn’t come about because of years of careful planning," he told Fast Company. "They came about because I put my Stanford classes online, and I had no idea what would ensue." But just a year later, it was clear that MOOCs were far from changing the world. A study by the University of Pennsylvania found that student engagement with courses fell drastically after the first week, and that completion rates averaged just 4%. By the end of that year, Thrun was giving interviews to outlets including Fast Company, saying Udacity had "a lousy product." He pivoted his company’s focus from changing the world to helping people in life-change careers. MOOCs are of course separate from the online classes offered by a university (for one thing, university classes aren’t free). But the volume of attention MOOCs generated made traditional educational institutions interested in offering online classes, as well, whatever the problems might be; many universities continued to design and expand their own online programs, even as enthusiasm for MOOCs waned. According to a 2016 report from the U.S. Department of Education, 5.5 million American students, or 25% of all college students, were taking some online classes. That was in 2013, and the number has continued to grow, if slowly. There are several reasons that online classes are particularly attractive to today’s colleges. For one, they have the potential to drastically increase revenue to institutions facing lower traditional enrollment. College enrollments fell by almost a million students between 2011 and 2013, the largest two-year drop since the U.S. Census Bureau began to collect these statistics in 1966. With an online course, a professor can design a curriculum once, and her university can run it again and again, with minimal updates, into the far future. The number of students isn’t limited to those who can physically move to your campus and attend classes, or dependent on the availability of a professor who'd maybe rather be writing a book. Anyone, anywhere, can take classes at any time. NYU's Maddox disputes that online classes are a revenue generator for schools. "It’s like cloud computing," he said. "It has all sorts of advantages, but the decision to go to cloud isn’t a lot of cost savings in the end." It’s the same with online education, he says. "To promote a high-quality, adaptive educational experience? We’re still seeing if that’s a cost savings in the end." In the best cases, universities have been learning lessons from MOOCs’ failures as they design their courses. For one, online classes tend to do best when students are a bit older and pursuing a specific educational goal. At the new Udacity, Thrun told me, the typical student is now 24 to 50 years old and looking to gain skills to help in their lives and careers. "They rarely come to us and say, ‘I want to learn something interesting,’" he explains. "This attitude increases their chances of success, because there’s something tangible they want from us. It’s not just self-enlightenment. That motivation is important." NYU also focuses its online offerings around graduate programs in areas that lend themselves to concrete truths and remote evaluation of progress, like computer science and engineering. Education providers are also realizing that online classes are especially attractive when they offer cost savings to the student. Not only is crushing student debt one of the primary reasons a student might second-guess college attendance, but a lower price tag matches the "less-than" perception of online classes. Recognizing this, Udacity now offers a complete master's degree in computer science through a partnership with Georgia Tech and AT&T for only $7,000. Many online programs are finding that students succeed best when they’re engaged with the content. "If you go to Stanford, and instead of teaching students and mentoring them, you just gave them all the books for all the classes, I think you’d see the same low completion rates" that many MOOCs have, Thrun told me. "To me, the MOOC is the book. The video book. It’s a component, but not all there is to it." Increasing engagement is also driving another Udacity project. Thrun said he is "actually experimenting with meetups," and looking at "what happens if someone takes charge [in a class]. And it does positively impact the outcomes." Students getting together to learn, in person, with "someone taking charge." Interesting (and familiar!) idea. So how do these trends look on the ground? At UF, officials tried to tick all these boxes with its online offerings, though it has faced several major problems. Elizabeth D. Capaldi Phillips was recruited from Arizona State University to run the new program, now dubbed UF Online (of which PaCE is a major part), only to resign after two months. Her position went unfilled for a year. The new head, Evangeline J. Tsibris Cummings, was appointed in July 2015, just months before PaCE admitted its first class of students. Meanwhile, the university cancelled its contract with Pearson to administer UF Online after it failed to attract out-of-state students who pay higher tuition. That first class ended up being very small, despite its reduced price tag. PaCE accepted 3,000 students its first year, but had only 235 people agree to take part in its online experiment (for comparison, about 50% of students accepted to UF in a more traditional way choose to enroll). Part of this, perhaps, was a focus in the first year on the fact that students hadn’t gotten full campus enrollment, and not that they had gotten into PaCE. "We got less than 10% of the students that we sent letters out to," Cummings told Fast Company, "but frankly I think that is tremendous, considering it was brand new. There was some consternation in the initial launch where folks didn't know what it was. I think there was some initial confusion about how it related to their on-campus admissions decision, and so we've learned from that." Paige Fry, a member of that class, remembers calling her mother in tears when she read her PaCE acceptance. "I didn’t know what it was or what it meant, and I was very upset," she told me over the phone. However, after evaluating UF’s program, she thought their online journalism program was a good match for her. Students of that first class were encouraged to move to Gainesville, where UF is located, she says, but were faced with a complex network of school activities in which they weren’t allowed to participate. They couldn’t use the school gym, but they could rush fraternities and sororities. They couldn’t live in the dorms, but could sit in the student section at football games. For two years, they are literally not allowed to officially participate in university classes. This was because the university had decided that in order to make the program as low cost as possible, PaCE students were not required to pay university activity fees. The school has since reconsidered this position, and now allows PaCE students to pay additional fees and use all student services. Fry eventually accepted, and took six classes her first semester, in which she got straight As. She also told me that many PaCE students semi-secretly sit in on the classes in which they’re officially enrolled online. "In general, I’m a self-motivated person," she told me. She works part-time, lives at home, and does her coursework whenever she wants. "I wake up at whatever time, and then sit down to do it," she told me, describing a pretty enviable daily routine. However, it must be said, it's a routine that’s not overly different from one I experienced in college and graduate school, which I attended in person. Fry is obviously the kind of focused, goal-driven person who succeeds in online education. But what about someone with less focus? In other words, a typical college freshman, who may feel a little overwhelmed? And even more specifically, one who didn’t have the drive in high school to excel enough to receive a regular enrollment slot at a state school like UF? "Honestly, if you asked me as a friend what recommendation I’d have about this, I’d have no recommendation at this point," said Thrun. "I can see the general concern: Oh my god, maybe it’s not the right fit, he’s not going to be successful, he’s going to lose interest, and he’s going to give up on college forever. I understand that logic, and, boy, I wish I had a word of wisdom." In general, Thrun says, the education a student gets can vary widely from program to program, and even class to class. UF, for instance, is one of the few that reports graduation rates: 63% of online students graduated within four years, just slightly under its 67% rate among traditional students. This is likely among the reasons its online bachelor's program comes in at number 11 in the nation in the rankings. But this doesn’t guarantee the success of the PaCE program. So, is Kinsella, whose best friend was also accepted to PaCE, going to attend? How does he feel about being part of this experiment? "Excited, obviously," he told me. "It felt great. It’s like, our favorite school." He’s confident he can succeed. "I’m going to be there, and it’s going to be a lot of fun, but it just comes down to me, myself."

Belonging to a group known as the Arctics, the Tanana Arctic, Oeneis tanana, is the first new butterfly species described from the Last Frontier in 28 years and may be its only endemic butterfly. University of Florida lepidopterist Andrew Warren suggests the butterfly could be the result of a rare and unlikely hybridization between two related species, both specially adapted for the harsh arctic climate, perhaps before the last ice age. Details of the finding are available online today in the Journal of Research on the Lepidoptera. Digging deeper into the Tanana Arctic's origins may reveal secrets about the geological history of arctic North America and the evolution of hybrid species, said Warren, who led the new study. "Hybrid species demonstrate that animals evolved in a way that people haven't really thought about much before, although the phenomenon is fairly well studied in plants," said Warren, senior collections manager at the McGuire Center for Lepidoptera and Biodiversity at the Florida Museum of Natural History on the UF campus. "Scientists who study plants and fish have suggested that unglaciated parts of ancient Alaska known as Beringia, including the strip of land that once connected Asia and what's now Alaska, served as a refuge where plants and animals waited out the last ice age and then moved eastward or southward from there. This is potentially a supporting piece of evidence for that." The new butterfly lives in the spruce and aspen forests of the Tanana-Yukon River Basin, most or all of which was never glaciated during the last ice age, about 28,000 to 14,000 years ago. Study researchers suggest that sometime in the past, two related species, the Chryxus Arctic, O. chryxus, and the White-veined Arctic, O. bore, may have mated and their hybrid offspring subsequently evolved into the Tanana Arctic. Then, during the coldest part of the last ice age, the Tanana Arctic and White-veined Arctic apparently remained in Beringia while the Chryxus Arctic was pushed south into the Rocky Mountains. This would mean all three species were once present in Beringia before the last ice age, Warren said. For more than 60 years the Tanana Arctic hid beneath scientists' noses incognito as its very similar relative the Chryxus Arctic, until Warren noticed its distinct characteristics while curating collections at the McGuire Center. In addition to expanded white specks on the underside of its penny-colored wings giving it a 'frosted' appearance, the Tanana Arctic is larger and darker than the Chryxus Arctic. It also has a unique DNA sequence, which is nearly identical to those found in nearby populations of White-veined Arctics, further supporting the hypothesis the new species may be a hybrid, Warren said. "Once we sequence the genome, we'll be able to say whether any special traits helped the butterfly survive in harsh environments," he said. "This study is just the first of what will undoubtedly be many on this cool butterfly." Warren said more field research is needed to investigate whether the Tanana Arctic also exists further east into the Yukon. Other species of Arctics are found in places like Russia and Siberia. The group is known for living in environments too cold and extreme for most other butterflies, and they survive in part thanks to a natural antifreeze their bodies produce. Because butterflies react extremely quickly to climate change, the new butterfly could serve as an early warning indicator of environmental changes in the relatively untouched areas of Alaska where the Tanana Arctic flutters. "This butterfly has apparently lived in the Tanana River valley for so long that if it ever moves out, we'll be able to say 'Wow, there are some changes happening,'" Warren said. "This is a region where the permafrost is already melting and the climate is changing." Warren plans to go back to the Yukon-Tanana basins next year in search of the Tanana Arctic. He hopes fieldwork in this rugged environment will result in fresh specimens to fully sequence the species' genome, which will reveal the butterfly's genetic history, including if it is truly a hybrid. "New butterflies are not discovered very often in the U.S. because our fauna is relatively well-known," Warren said. "There are around 825 species recorded from the U.S. and Canada. But with the complex geography in the western U.S., there are still going to be some surprises." Explore further: New Jamaica butterfly species emphasizes need for biodiversity research

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