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On Friday 20 September, millions of people led by Greta Thunberg and students from Sydney to Delhi, Melbourne to London and New York, will march for urgent action on climate change. Follow for all the latest school strike 4 climate news

Absolutely huge turnout in Geelong where they’re singing and chanting.

At Geelong City Hall for the #ClimateStrike . Huge turnout pic.twitter.com/AA5Pbdo151

“No planet B” song at Geelong #ClimateStrike pic.twitter.com/5xrMAXkSzc

Townsville locals #Strike4Climate, not a single southern latte-sipper in sight. pic.twitter.com/VjAYF9qfrB

First Barnesy now The Oils:

We support today’s #climatestrike - "it happens to be an emergency". Look at these average annual temps (dark red = hottest years). For everyone, especially the young, we are now at the crossroads. pic.twitter.com/k9XZoL44oE

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THURSDAY 19. SEPTEMBER 2019


Two target markers deployed around Ryugu ahead of lander’s planned descent next month

Japan’s Hayabusa 2 spacecraft has deployed two target markers around asteroid Ryugu. The deployment took place at 5.17pm BST on 17 September from an altitude of 1km. In the minuscule gravity of the asteroid, the unpowered markers are still falling to its surface. They are expected to land sometime over the weekend or early next week at the latest.

The 10cm-wide markers are covered in a highly reflective material that makes them easy to observe from the main spacecraft, which has now risen to a height of 20km (12.4 miles). By tracking their descent, planetary scientists can deduce the precise gravitational field that the asteroid generates, which reveals its internal structure. Hayabusa 2 arrived at Ryugu on 27 June 2018. It has already released three small rovers to the surface and performed two touchdowns to collect surface material.

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River ecosystems are highly biodiverse, influence global biogeochemical cycles, and provide valued services. However, humans are increasingly degrading fluvial ecosystems by altering their streamflows. Effective river restoration requires advancing our mechanistic understanding of how flow regimes affect biota and ecosystem processes. Here, we review emerging advances in hydroecology relevant to this goal. Spatiotemporal variation in flow exerts direct and indirect control on the composition, structure, and dynamics of communities at local to regional scales. Streamflows also influence ecosystem processes, such as nutrient uptake and transformation, organic matter processing, and ecosystem metabolism. We are deepening our understanding of how biological processes, not just static patterns, affect and are affected by stream ecosystem processes. However, research on this nexus of flow-biota-ecosystem processes is at an early stage. We illustrate this frontier with evidence from highly altered regulated rivers and urban streams. We also identify research challenges that should be prioritized to advance process-based river restoration.

Structures known as 'time crystals' -- which repeat in time as conventional crystals repeat in space -- have recently captured the interest and imagination of researchers across disciplines. The concept has emerged from the context of quantum many-body systems, but physicists have now developed a versatile framework that clarifies connections to classical works dating back nearly two centuries, thus providing a unifying platform to explore seemingly dissimilar phenomena.

To best serve the clinical needs of individuals with MS, neuropsychological testing needs to be viewed in larger context comprising non-cognitive variables, such as motor ability and demographic values, fatigue and depression, and disease activity and level of disability, as well as person-specific factors such as personality and coping styles.

Birds across the U.S. are disappearing, though many of us probably haven’t noticed.

Over the past half century, North American bird populations have undergone a quiet crisis, with scientists estimating the continent to have lost 29% of its total avian population, as revealed a new paper published in the journal Science on Thursday. That’s a loss of nearly 3 billion birds in the last half century.

“I would call it an imminent disaster,” says Ken Rosenberg, a conservation scientist at the Cornell Lab of Ornithology and the American Bird Conservancy, and the lead author on Thursday’s paper in Science. “We need to do something about it now, and we need to pay attention.”

Scientists have been tracking populations of threatened and endangered birds for years, and noted that some populations were in decline. But they assumed that those threatened species were being replaced by “generalist species,” or more adaptable birds that were better suited to deal with man-made changes to their environment.

What’s stunning in these newest findings is the fact that broad population declines are being recorded across North American birds as a whole, in a trend not confined to any one species or ecological niche.

“The bulk of that loss is occurring in the common species,” says Rosenberg. “It’s across every habitat.”

Grassland bird species showed the largest impacts, with more than half their number, over 700 million breeding individuals across 31 species, lost since 1970. Birds living in forests also showed massive hits, with total losses of more than a billion birds.

“Birds are really facing an unprecedented crisis due to human activity,” says Nicole Michel a senior quantitative ecologist with the National Audubon Society. “We really need to take action quickly.”

Scientists believe that the loss of bird populations is due to a variety of factors, chief among them habitat loss, intensifying agricultural production and disruption of coastal ecosystems, all of which are exacerbated by the intensifying impacts of anthropogenic climate change. In particular, the authors of the paper believe that the stunning losses of grassland bird populations are driven in large part by increased pesticide usage and habitat loss due to agriculture.

Not all species showed population declines, and many even showed gains over the decades, but the overall drop in bird populations was startling. Those broad declines may not be readily visible to the average bird watcher, but over decades of data the devastating trend becomes all too clear.

“The loss of that magnitude could signal an unraveling of ecological processes,” says Rosenberg. “People need to start paying attention to the birds around them, because if the loss continues we’re really going to notice it and feel it.”

To compile the report, Rosenberg and his colleagues looked at data from sources that tracked 529 species of birds in the continental United States and Canada, spanning far flung geographic areas and habitats. The scientists relied in large part on information gathered through the North American Breeding Birds Survey, a longstanding partnership between scientists and amateur bird watchers. Those efforts showed persistent declines in bird populations. And when the scientists used supercomputers to examined data from weather radar, which for the past decade has recorded the biomass of migrating birds passing overhead at night, they discovered similar population declines.

“This is groundbreaking because of the incorporation of the radar data,” explains Michel. That information, Michel explains, allowed scientists to count bird populations that breed in sparsely populated northern regions where people aren’t necessarily able to reach them, and also enabled the report authors to independently verify the survey data that showed massive population losses.

There was one ray of hope in the paper’s overall gloomy findings — wetland birds showed gains in population, probably due in part to the billions of dollars in investment that have been poured into wetlands protection and restoration. For the authors, those gains show that this crisis does not necessarily need to become a full-blown catastrophe, assuming government and citizens take action to protect bird species from further impacts.

“We’re at a point where we can reverse these declines,” says Rosenberg. “We need to be acting now.”

Public action is urgently needed, but Rosenberg also notes that there are measures that individual citizens can take to help sustain bird populations, like planting native species in gardens and keeping cats indoors.

For Michel, successes like the recovery of raptor populations after DDT, a potent pesticide, was banned show that we have not yet reached the point of no return for North American birds.

“This is a crisis and a warning call,” she says. “But birds are resilient if you give them a chance.”

Is your kid obsessed with video games and hanging out with questionable friends? These are common traits for involvement in cybercrime, among other delinquencies. New research from Michigan State University identified characteristics and gender-specific behaviors in kids that could lead them to become juvenile hackers.