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Massive corals are characteristically ball- or boulder-shaped and relatively slow-growing. Because they have very stable profiles, massive corals are seldom damaged by strong wave action unless they are dislodged from their holdfasts.
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Our peer-reviewed reports present the evidence-based consensus of committees of experts. Published proceedings record the presentations and discussions that take place at hundreds of conferences, workshops, symposia, forums, roundtables, and other gatherings every year. And, our prestigious journals publish the latest scientific findings on a wide range of topics.
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Data mining of massive data sets is transforming the way we think about crisis response, marketing, entertainment, cybersecurity and national intelligence. Collections of documents, images, videos, and networks are being thought of not merely as bit strings to be stored, indexed, and retrieved, but as potential sources of discovery and knowledge, requiring sophisticated analysis techniques that go far beyond classical indexing and keyword counting, aiming to find relational and semantic interpretations of the phenomena underlying the data.
The Chapter Skim search tool presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter. You may select key terms to highlight them within pages of each chapter.
Scott Weidman, director of the Board on Mathematical Science and their Applications at the NRC, explains the charge and key recommendation of the report along with the challenges and opportunties the Massive Data presents.
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Emotional states can be transferred to others via emotional contagion, leading people to experience the same emotions without their awareness. Emotional contagion is well established in laboratory experiments, with people transferring positive and negative emotions to others. Data from a large real-world social network, collected over a 20-y period suggests that longer-lasting moods (e.g., depression, happiness) can be transferred through networks [Fowler JH, Christakis NA (2008) BMJ 337:a2338], although the results are controversial. In an experiment with people who use Facebook, we test whether emotional contagion occurs outside of in-person interaction between individuals by reducing the amount of emotional content in the News Feed. When positive expressions were reduced, people produced fewer positive posts and more negative posts; when negative expressions were reduced, the opposite pattern occurred. These results indicate that emotions expressed by others on Facebook influence our own emotions, constituting experimental evidence for massive-scale contagion via social networks. This work also suggests that, in contrast to prevailing assumptions, in-person interaction and nonverbal cues are not strictly necessary for emotional contagion, and that the observation of others' positive experiences constitutes a positive experience for people.
Students sitting in a classroom attending the final day of the Advanced Helicopter Rescue School also heard the call. The students leapt at the chance to assist in the rescue. Any one of the swimmers could have gone, but ultimately it was a game of rock, paper, scissors that allowed Branch to join the senior instructors in the rescue.
Once the aircrew arrived on scene, they witnessed 20-foot seas and extremely high windspeeds. The Motor Life Boats passed survival equipment, including a personal flotation device (PFD) to the distressed mariner, but ultimately the sea state was too severe for them to safely execute a rescue. Branch was lowered into the water and swam to the vessel. Once he arrived near the boat, the man in distress pointed to a breaking wave. Video footage form the incident caught Branch diving underneath the water just as the massive wave rolled the vessel and ejected the man in distress into the water.
I think the rescue went smooth though. What we learn doing AHRS is standardized and honestly, I think going through the training well prepared me for the rescue. The aircrew was mostly instructors, so I was with seasoned professionals, and it gave me peace of mind.
Branch and other students graduated AHRS just three hours after completing the rescue. His dedication to completing the mission was selfless and displays how teamwork in the Coast Guard is necessary. Although the rescue garnered him national attention, Branch only considers himself one moving part in the machine of Coast Guard rescuers. No job goes unnoticed in a group effort to save a life.
JWST revealed supermassive black holes that appear too massive for the small galaxies that host them. By breaking long-known cosmic scales, these objects are letting astronomers probe the primeval cosmos.
In nearby, mature galaxies like our Milky Way, the total mass of stars vastly outweighs the mass of the big black hole found at the galaxy's center by about 1000 to 1. In the newfound distant galaxies, however, that mass difference drops to 100 or 10 to 1, and even to 1 to 1, meaning the black hole can equal the combined mass of its host galaxy's stars.
This picture of unexpectedly massive black holes in fledgling galaxies comes from the James Webb Space Telescope (JWST), NASA's latest flagship observatory. Until JWST, which launched in late 2021, astronomers were generally limited in their studies of distant black holes to stupendously bright quasars, composed of monster, matter-devouring black holes that completely outshine the stars in their host galaxies.
"With JWST, we can now finally observe lower-mass, yet still supermassive black holes in small, faraway galaxies, and we can see the stars in these host galaxies as well," says Fabio Pacucci, a Clay Fellow at the Center for Astrophysics Harvard & Smithsonian (CfA). "This allows us to study, for the first time, early black holes and their host galaxies as they evolve together."
Pacucci is the lead author of a new study published in The Astrophysical Journal Letters reporting the findings, and presented these results at the 243rd meeting of the American Astronomical Society in New Orleans, LA.
"We have learned that distant, young galaxies violate the relation between black hole mass and stellar mass that is very well established in nearby, mature galaxies: these primeval black holes are undoubtedly overmassive relative to the stellar population of their hosts," says Roberto Maiolino, a professor at the University of Cambridge (UK), and co-author of the study. "With JWST, it will be possible to pinpoint how the first supermassive black holes formed by finding black holes that are farther and smaller than those found so far, and which our study predicts to be quite abundant."
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