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Why young sunflowers follow the sun

first_imgEvery day, young sunflowers follow the sun like spectators at an incredibly slow tennis match. But scientists have never known why, or why the tracking stops when they become adults. Now, a new study suggests that this daily sun worship is guided by circadian rhythms during development. In a series of experiments, scientists tied down young plants to prevent them from moving or rotated them so they were facing the wrong way when the sun rose. When the plants’ normal movements were thwarted, they grew far more slowly than regular sunflowers, with about a 10% decrease in both biomass and leaf area. Researchers say the rhythmic tracking helps the plants grow bigger, allowing them to add cells on whichever side is doing the “stretching”: the east side during the day and the west side at night. When the sunflowers finally settle down and stop this daily tracking, their position also gives them an advantage, researchers report this week in Science. A second set of experiments showed that mature plants’ permanent eastward orientation makes for warmer flower faces, which may be responsible for a large increase in pollinator visits—five times more than in mature plants that face west. Looks like following the sun is more than just a spectator sport!last_img read more


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Struggling to make ends meet Indias earlycareer scientists take to the streets

first_img Sign up for our daily newsletter Get more great content like this delivered right to you! Country By Sanjay KumarJan. 2, 2019 , 12:40 PM Struggling to make ends meet, India’s early-career scientists take to the streets Atul Pradhan Scientists protested at the Indian Institute of Science in Bengaluru on 21 December 2018. Emailcenter_img The new year is likely to see more protests by young Indian researchers struggling to make ends meet—which could include hunger strikes. Their leaders will meet on Thursday in New Delhi to chart a new course of action for their movement, which has taken to the streets several times the past few months. During the last protest, on 21 December 2018, thousands of researchers demonstrated at research institutions and universities around the country and at the federal science ministry in New Delhi.The scientists say their fellowship stipends are far too low to get by and often arrive 6 or even 12 months late. Prakash Javdekar, India’s minister of human resource development, acknowledged on 26 December 2018 that there had been backlogs, but said those have been addressed and cleared. The researchers called his statement a bluff; moreover, if the government wants to retain young talent, they say, it needs to increase the fellowships by 80% and provide for annual increases to make up for the rising cost of living.Many Indian agencies, including the University Grants Commission, the Council of Scientific & Industrial Research, and the Department of Science & Technology, provide stipends to early-career scientists who have passed an eligibility test. Ph.D. students receive just 25,000 rupees ($356) monthly the first 2 years and 28,000 rupees the following 3 years; research associates make 36,000 rupees to 40,000 rupees per month. Those not provided with a hostel room also get a modest rent allowance. 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Required fields are indicated by an asterisk (*) The amounts haven’t gone up in 4 years, even though housing costs have risen sharply. “In cities like Delhi or Bengaluru, rents automatically shoot up by 10% to 15% every [10] months, and many researchers coming from other cities don’t get hostels,” says Lal Chandra Vishwakarma, chairperson of the Society of Young Scientists at the All India Institute of Medical Sciences in New Delhi. The long delays in payment amount to “enormous psychological harassment,” says Vishwakarma, who has led the recent protests.One young researcher at Delhi University who asked not to be named says she knows a fellow researcher who sometimes skips meals for days while his fellowship money is delayed. “Instead of focusing on research, students are forced to waste precious time chasing their fellowship money,” the researcher says. Researchers say they face enormous societal pressure to do better financially as others of their age and education level take up well-paying jobs outside academe.The situation is even worse for the large number of researchers enrolled in Ph.D. programs who have not passed the tests for a fellowship; they get almost no financial support. A nanotechnology researcher at the Rajiv Gandhi Technical University in Bhopal, India, says he receives no payments at all from his institute or the state government and even pays for his experiments from his own pocket.The Indian government’s principal scientific adviser, Krishnaswamy VijayRaghavan, acknowledges the problems. “While the situation is much better than a few years ago, there is much to be done and we recognize that and are addressing the matter,” he told ScienceInsider. “As we increase the footprint of science, our personnel costs go up,” VijayRaghavan says. “But overall we are working hard to increase support for students at all levels.”Ashutosh Sharma, secretary of India’s Department of Science & Technology and a nanotechnologist at the Indian Institute of Technology in Kanpur, is sympathetic to the demands as well. “I personally support the idea of regular increases instead of every 4 years,” he says. Sharma says he’s hopeful the next raise will come soon but alludes to the complexities of bringing together all of the government agencies involved—including the finance ministry, which controls the purse strings.Indian researchers hope general elections to be held in April or May will help their cause. Prime Minister Narendra Modi’s popularity has dropped recently—his Bharatiya Janata Party lost all five state elections held in December 2018—and alienating younger voters and the scientific community could hurt Modi’s chances to stay in power, researchers say.last_img read more