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Showing posts from November, 2020

Black carbon and other pollution seeds clouds. We’re just starting to understand the climate implications

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Particles   swirling around our atmosphere   add to   climate change, yet much about how they interact with  sunlight  and influence the seeding of clouds remains puzzling. Studies are lifting the lid on how these tiny   particles influence something as big as climate  by  analysing them from jet aircraft ,  satellites  and ground measurements .   The leading cause of climate change is rising levels of carbon dioxide in the atmosphere. This rise has been happening since the start of the Industrial Revolution  and w e now know a lot about how this gas behaves, traps heat and warms the Earth.  A far more mysterious influence on climate comes from particles – or aerosols – suspended in air. Especially important is black carbon, the soot wafting off from burning vegetation and traffic fumes. This black stuff ranks as the second largest contributor to climate change. But it is very different from carbon dioxide. ...

Researchers say they’ve identified gene responsible for cellular aging

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Cellular reprogramming can reverse the aging that leads to a decline in the activities and functions of mesenchymal stem/stromal cells (MSCs). This is something that scientists have known for a while. But what they had not figured out is which molecular mechanisms are responsible for this reversal. A study released today in STEM CELLS appears to have solved this mystery. It not only enhances the knowledge of MSC aging and associated diseases, but also provides insight into developing pharmacological strategies to reduce or reverse the aging process. The research team, made up of scientists at the University of Wisconsin-Madison, relied on cellular reprogramming – a commonly used approach to reverse cell aging – to establish a genetically identical young and old cell model for this study. “While agreeing with previous findings in MSC rejuvenation by cellular reprogramming, our study goes further to provide insight into how reprogrammed MSCs are regulated molecularly to ameliorate the ...

Most popular American movies depict an unhealthy diet

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It’s no surprise that most people in the U.S. don’t follow a healthy diet. But Stanford psychologists wanted to go deeper to find out why people don’t eat healthier even when they know it’s better for them. So they looked at an influential force in American popular culture – movies – to see how they depict foods and beverages on-screen to the public. Video by Kurt Hickman Stanford researchers examined the 250 top-grossing American movies of recent decades and found the on-screen foods and beverages largely failed U.S. government nutrition recommendations and U.K. youth advertising standards. It turns out: not very well. In a new study, the Stanford researchers looked at the 250 top-grossing Hollywood movies between 1994 and 2018 – including “Black Panther,” “Avatar” and “Titanic” – to quantify the foods and beverages shown on-screen and see how well they align with what the government recommends people eat and what Americans are actually eating. “Movies portray the types of fo...

Ultrafast way to manufacture perovskite solar modules

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Most solar cells today are made with refined silicon that turns sunlight into clean electricity. Unfortunately, the process of refining silicon is far from clean, requiring vast amounts of energy from carbon-emitting power plants. For a greener alternative to silicon, researchers have focused on thin-film perovskites – low-cost, flexible solar cells that can be produced with minimal energy and virtually no CO 2  emissions. While perovskite solar cells are promising, significant challenges need to be addressed before they can become commonplace, not least of which is their inherent instability, which makes manufacturing them at scale difficult. “Perovskite solar technology is at a crossroads between commercialization and flimflammery,” said Stanford University postdoctoral scholar  Nick Rolston . “Millions of dollars are being poured into startups. But I strongly believe that in the next three years, if there isn’t a breakthrough that extends cell lifetimes, that money will...

Live tracker notes COVID cases, deaths by congressional districts

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Researchers at the  Harvard Center for Population and Development Studies ,  Harvard Center for Geographic Analysis  at the  Institute for Quantitative Social Science,  and  Microsoft AI for Health  have created a COVID-19 live tracker that monitors the current status of virus cases and deaths, as well as the reduction of new cases, in U.S. congressional districts. It is the first compilation of this data, which could be key for elected officials and their constituents to monitor and develop testing strategies, vaccine deployment strategies, and other measures to enable their districts to open safely. “By connecting previously separate reporting geographies for public health and electoral data, this data set represents an important effort,” said  Gary King , director of the Institute for Quantitative Social Science, and Weatherhead University Professor at Harvard. “As the COVID-19 pandemic continues to spiral out of control in the U.S. (and el...

Reconstructing vertebrates rise from the water to land

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It’s hard to overstate how much of a game-changer it was when vertebrates first rose up from the waters and moved onshore about 390 million years ago. That transition led to the rise of the dinosaurs and all the land animals that exist today. “Being able to walk around on land essentially set the stage for all biodiversity and established modern terrestrial ecosystems,” said Stephanie Pierce, Thomas D. Cabot Associate Professor of Organismic and Evolutionary Biology and curator of vertebrate paleontology in the Museum of Comparative Zoology. “It represents an incredibly important period of time in evolutionary history.” Scientists have been trying for more than a century to unravel exactly how this remarkable shift took place, and their understanding of the process is largely based on a few rare, intact fossils with anatomical gaps between them. A new study from Pierce and Blake Dickson, Ph.D. ’20, looks to provide a more thorough view by zeroing in on a single bone: the humerus...

Coated nanoparticles survive immune system and deliver drugs

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Nanoparticles are promising drug delivery tools, offering the ability to administer drugs directly to a specific part of the body and avoid the awful side effects so often seen with chemotherapeutics. But there’s a problem. Nanoparticles struggle to get past the immune system’s first line of defense: proteins in the blood serum that tag potential invaders. Because of this, only about 1 percent of nanoparticles reach their intended target. “No one escapes the wrath of the serum proteins,” said Eden Tanner, a former postdoctoral fellow in bioengineering at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS). Now, Tanner and a team of researchers led by Samir Mitragotri, the Hiller Professor of Bioengineering and Hansjorg Wyss Professor of Biologically Inspired Engineering at SEAS, have developed an ionic forcefield that prevents proteins from binding to and tagging nanoparticles. In mouse experiments, nanoparticles coated with the ionic liquid survived s...

When ice sheets melt, it’s a seesaw effect

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To see how deeply interconnected the planet truly is, look no further than the massive ice sheets on the Northern Hemisphere and South Pole. Thousands of miles apart, they are hardly next-door neighbors, but according to new research from a team of international scientists — led by Natalya Gomez, Ph.D. ’14, and including Harvard Professor  Jerry X. Mitrovica  — what happens in one region has a surprisingly direct and outsized effect on the other, in terms of ice expanding or melting. The analysis, published in  Nature , shows for the first time that changes in the Antarctic ice sheet were caused by the melting of ice sheets in the Northern Hemisphere. The influence was driven by sea-level changes caused by the melting ice in the north during the past 40,000 years. Understanding how this works can help climate scientists grasp future changes as global warming increases the melting of major ice sheets and ice caps, researchers said. The study models ho...

Scientists develop new gene therapy for eye disease

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Scientists from Trinity have developed a new gene therapy approach that offers promise for one day treating an eye disease that leads to a progressive loss of vision and affects thousands of people across the globe. The study, which involved a collaboration with clinical teams in the Royal Victoria Eye and Ear Hospital and the Mater Hospital, also has implications for a much wider suite of neurological disorders associated with ageing. The scientists  publish their results today  in leading journal,  Frontiers in Neuroscience. Characterised by degeneration of the optic nerves, DOA typically starts to cause symptoms in patients in their early adult years. These include moderate vision loss and some colour vision defects, but severity varies, symptoms can worsen over time and some people may become blind. There is currently no way to prevent or cure DOA. A gene ( OPA1 ) provides instructions for making a protein that is found in cells and tissues throughout the body, a...

California GHG in the plus column. Emissions-reduction steps state can take to get back on track

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California has been a leader when it comes to climate-change-correction work, meaning efforts by the state to reduce annual greenhouse gas (GHG) emissions output have been working. But the most recent numbers tell a slightly different tale. This is reflected in the latest (2018) California GHG emissions inventory. Compared to annual Golden State GHG output the year prior (2017) which, by the way, was 424.5 million metric tons of carbon dioxide equivalent (MMTCO 2 e) emissions, 2018’s output was a slightly higher 425.3 MMTCO 2 e, a 0.8 MMTCO 2 e gain. 1 As a gain, be it small, modest or substantial, state GHG emissions output is headed in the wrong direction. Listed below are the categories with their corresponding numbers 2 (in MMTCO 2 e) 2018 versus 2017: Agriculture: 32.57 (2018); 32.32 (2017) Commercial and Residential: 41.37 (2018); 41.27 (2017) Electric Power: 63.11 (2018); 62.13 (2017) High Global Warming Potential (gases): 20.46 (2018); 19.99 (2017) Industrial: 89.18 ...