Rising temperatures hinder Indian wheat production

Geographers at the University of Southampton have found a link between increasing average temperatures in India and a reduction in wheat production.Researchers Dr John Duncan, Dr Jadu Dash and Professor Pete Atkinson have shown that recent warmer temperatures in the country’s major wheat belt are having a negative effect on crop yield. More specifically, they found a rise in nighttime temperatures is having the most impact.Dr Jadu Dash comments: “Our findings highlight the vulnerability of India’s wheat production system to temperature rise, which is predicted to continue in the coming decades as a consequence of climate change. We are sounding an early warning to the problem, which could have serious implications in the future and so needs further investigation.”The researchers used satellite images taken at weekly intervals from 2002 to 2007 of the wheat growing seasons to measure ‘vegetation greenness’ of the crop — acting as an indicator of crop yield. The satellite imagery, of the north west Indo-Gangetic plains, was taken at a resolution of 500m squared — high enough to capture variations in local agricultural practices. The data was then compared with climate and temperature information for the area to examine the effect on growth and development of the crop.The study, published in the journal Global Change Biology, found that:warmer temperature events have reduced crop yield in particular, warmer temperatures during the reproductive and grain-filling (ripening) periods had a significant negative impact on productivity warmer minimum daily temperatures (nighttime temperatures) had the most significant impact on yield In some areas of the Indian wheat belt, growers have been bringing forward their growing season in order to align the most sensitive point of the crop growth cycle with a cooler period. However, the researchers have also shown that in the long-term this will not be an effective way of combating the problem, because of the high level of average temperature rise predicted for the future.Dr Dash comments: “Our study shows that, over the longer period, farmers are going to have to think seriously about changing their wheat to more heat tolerant varieties in order to prevent temperature-induced yield losses.”Currently in India, 213 million people are food insecure and over 100 million are reliant on the national food welfare system, which uses huge quantities of wheat. This underlines how crucial it is to consider what types of wheat need to be grown in the coming decades to secure production.”We hope that soon, we will be able to examine agricultural practices in even greater detail — with the launch of the European Space Agency’s Sentinel satellites which will provide regular data at even higher spatial resolution.”Story Source:The above story is based on materials provided by University of Southampton. Note: Materials may be edited for content and length.

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Self-healing engineered muscle grown in the laboratory

Biomedical engineers have grown living skeletal muscle that looks a lot like the real thing. It contracts powerfully and rapidly, integrates into mice quickly, and for the first time, demonstrates the ability to heal itself both inside the laboratory and inside an animal.The study conducted at Duke University tested the bioengineered muscle by literally watching it through a window on the back of living mouse. The novel technique allowed for real-time monitoring of the muscle’s integration and maturation inside a living, walking animal.Both the lab-grown muscle and experimental techniques are important steps toward growing viable muscle for studying diseases and treating injuries, said Nenad Bursac, associate professor of biomedical engineering at Duke.The results appear the week of March 25 in the Proceedings of the National Academy of Sciences Early Edition.”The muscle we have made represents an important advance for the field,” Bursac said. “It’s the first time engineered muscle has been created that contracts as strongly as native neonatal skeletal muscle.”Through years of perfecting their techniques, a team led by Bursac and graduate student Mark Juhas discovered that preparing better muscle requires two things — well-developed contractile muscle fibers and a pool of muscle stem cells, known as satellite cells.Every muscle has satellite cells on reserve, ready to activate upon injury and begin the regeneration process. The key to the team’s success was successfully creating the microenvironments — called niches — where these stem cells await their call to duty.”Simply implanting satellite cells or less-developed muscle doesn’t work as well,” said Juhas. “The well-developed muscle we made provides niches for satellite cells to live in, and, when needed, to restore the robust musculature and its function.”To put their muscle to the test, the engineers ran it through a gauntlet of trials in the laboratory. By stimulating it with electric pulses, they measured its contractile strength, showing that it was more than 10 times stronger than any previous engineered muscles. They damaged it with a toxin found in snake venom to prove that the satellite cells could activate, multiply and successfully heal the injured muscle fibers.Then they moved it out of a dish and into a mouse.With the help of Greg Palmer, an assistant professor of radiation oncology in the Duke University School of Medicine, the team inserted their lab-grown muscle into a small chamber placed on the backs of live mice. The chamber was then covered by a glass panel. Every two days for two weeks, Juhas imaged the implanted muscles through the window to check on their progress.By genetically modifying the muscle fibers to produce fluorescent flashes during calcium spikes — which cause muscle to contract — the researchers could watch the flashes become brighter as the muscle grew stronger.”We could see and measure in real time how blood vessels grew into the implanted muscle fibers, maturing toward equaling the strength of its native counterpart,” said Juhas.The engineers are now beginning work to see if their biomimetic muscle can be used to repair actual muscle injuries and disease.”Can it vascularize, innervate and repair the damaged muscle’s function?” asked Bursac. …

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Study suggests non-uniform climate warming globally

A recent University of Oklahoma study of five decades of satellite data, model simulations and in situ observations suggests the impact of seasonal diurnal or daily warming varies between global regions affecting many ecosystem functions and services, such as food production, carbon sequestration and climate regulation. The effects of non-uniform climate warming on terrestrial ecosystems is a key challenge in carbon cycle research and for those making future predictions.Jianyang Xia, a research associate in the OU College of Arts and Sciences, says the impact of non-uniform warming is just one aspect of climate change. Shifts in precipitation and disturbances, such as wildfires, increases in the frequency of extreme temperature events, large year-to-year shifts in temperature and shifts in regional climate zones can be expected as the climate warms. A complete understanding of the consequences of climate change for carbon cycling on land requires insight into the impact of all these changes on the ecosystem.As this study suggests, the rate of climate warming varies by season and region, and between day and night. A synthesis of air temperature data from across the world reveals a greater rate of warming in winter than in summer in northern and high latitudes, but the inverse is true in some tropical regions.Also, the data show a decline in the daily temperature range over 51 percent of the globe and an increase over only 13 percent, because night-time temperatures in most locations have risen faster than daytime temperatures.From the data analyzed, a number of trends emerged in non-uniform climate warming for ecosystem carbon cycling. Spring warming will enhance ecosystem carbon uptake at high latitudes and diminish the magnitude of seasonal temperature change in these regions. Summer and autumn warming are more likely to reduce ecosystem carbon uptake in tropical ecosystems and amplify the magnitude of seasonal temperature change.The contrasting impacts of day- and night-time warming on plant carbon gain and loss are apparent in many regions. Day warming increases carbon uptake in most areas of tundra and boreal forests but decreases it in most grasslands and deserts. Night warming enhances carbon uptake in arid ecosystems, such as grassland desert but has negative impacts in other regions.Most of the existing temperature-manipulation experiments relied on continuous and uniform warming, so further research is needed to predict the effects of non-uniform climate warming on terrestrial carbon cycling. A paper on this study was accepted for early online publication on February 23, 2014, by Nature Geoscience.Story Source:The above story is based on materials provided by University of Oklahoma. …

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Drones open way to new world of coral research

Oct. 16, 2013 — Camera-equipped flying robots promise new insights into climate change effects on important ecosystems.Stanford aeronautics graduate student Ved Chirayath photographs coral reefs from below the water using a 360-degree camera.Like undiscovered groves of giant redwoods, centuries-old living corals remain unmapped and unmeasured. Scientists still know relatively little about the world’s biggest corals, where they are and how long they have lived.The secret to unlocking these mysteries may lie with a shoebox-size flying robot.The robot in question is a four-rotor remote-controlled drone developed by Stanford aeronautics graduate student Ved Chirayath. The drone is outfitted with cameras that can film coral reefs from up to 200 feet in the air. Chirayath teamed up with Stanford Woods Institute Senior Fellow Stephen Palumbi to pioneer the use of drone technology to precisely map, measure and study shallow-water reefs off Ofu Island in American Samoa.”Until now the challenges have been too high for flying platforms like planes, balloons and kites,” Palumbi said. “Now send in the drones.”Chirayath, who also works as a scientist at NASA’s Ames Research Center, analyzes the drone’s footage using software he designed. The software removes distortions caused by surface wave movements and enhances resolution. To link the drone aerial footage to close-up images of corals, Chirayath and his colleagues are photographing reefs from below the water using a 360-degree camera. The result is a centimeter-scale optical aerial map and stunning gigapixel panoramic photographs of coral heads that stitch together thousands of images into one.Surveys and maps of rainforests have resulted in new understanding of the vital role these ecosystems play in sustaining the biosphere. Detailed coral maps could do the same, allowing scientists to conduct precise species population surveys over large areas and assess the impact of climate change.The window of time to study these mysterious ecosystems, which provide sustenance and livelihoods to a billion people, may be closing. …

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