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    [–] Einstein proved right in another galaxy - A team of astronomers used a nearby galaxy as a gravitational lens to make a precise test of gravity on astronomical length scales, to show that gravity in this galaxy behaves as predicted by Albert Einstein’s general theory of relativity. mvea 0 points ago in science

    The title of the post is a copy and paste from the title, second and fifth paragraphs of the linked academic press release here :

    Einstein proved right in another galaxy

    By combining data taken with NASA’s Hubble Space Telescope and the European Southern Observatory’s Very Large Telescope, their results show that gravity in this galaxy behaves as predicted by Albert Einstein’s general theory of relativity, confirming the theory’s validity on galactic scales.

    A team of astronomers, led by Dr Thomas Collett of the Institute of Cosmology and Gravitation at the University of Portsmouth, used a nearby galaxy as a gravitational lens to make a precise test of gravity on astronomical length scales.

    Journal Reference:

    Thomas E. Collett, Lindsay J. Oldham, Russell J. Smith, Matthew W. Auger, Kyle B. Westfall, David Bacon, Robert C. Nichol, Karen L. Masters, Kazuya Koyama, Remco van den Bosch.

    A precise extragalactic test of General Relativity.

    Science, 2018; 360 (6395): 1342-1346

    DOI: 10.1126/science.aao2469

    Link: http://science.sciencemag.org/content/360/6395/1342

    Testing General Relativity on galaxy scales

    Einstein's theory of gravity, General Relativity (GR), has been tested precisely within the Solar System. However, it has been difficult to test GR on the scale of an individual galaxy. Collett et al. exploited a nearby gravitational lens system, in which light from a distant galaxy (the source) is bent by a foreground galaxy (the lens). Mass distribution in the lens was compared with the curvature of space-time around the lens, independently determined from the distorted image of the source. The result supports GR and eliminates some alternative theories of gravity.

    Abstract

    Einstein’s theory of gravity, General Relativity, has been precisely tested on Solar System scales, but the long-range nature of gravity is still poorly constrained. The nearby strong gravitational lens ESO 325-G004 provides a laboratory to probe the weak-field regime of gravity and measure the spatial curvature generated per unit mass, γ. By reconstructing the observed light profile of the lensed arcs and the observed spatially resolved stellar kinematics with a single self-consistent model, we conclude that γ = 0.97 ± 0.09 at 68% confidence. Our result is consistent with the prediction of 1 from General Relativity and provides a strong extragalactic constraint on the weak-field metric of gravity.

    [–] Einstein proved right in another galaxy - A team of astronomers used a nearby galaxy as a gravitational lens to make a precise test of gravity on astronomical length scales, to show that gravity in this galaxy behaves as predicted by Albert Einstein’s general theory of relativity. mvea 1 points ago in space

    The title of the post is a copy and paste from the title, second and fifth paragraphs of the linked academic press release here :

    Einstein proved right in another galaxy

    By combining data taken with NASA’s Hubble Space Telescope and the European Southern Observatory’s Very Large Telescope, their results show that gravity in this galaxy behaves as predicted by Albert Einstein’s general theory of relativity, confirming the theory’s validity on galactic scales.

    A team of astronomers, led by Dr Thomas Collett of the Institute of Cosmology and Gravitation at the University of Portsmouth, used a nearby galaxy as a gravitational lens to make a precise test of gravity on astronomical length scales.

    Journal Reference:

    Thomas E. Collett, Lindsay J. Oldham, Russell J. Smith, Matthew W. Auger, Kyle B. Westfall, David Bacon, Robert C. Nichol, Karen L. Masters, Kazuya Koyama, Remco van den Bosch.

    A precise extragalactic test of General Relativity.

    Science, 2018; 360 (6395): 1342-1346

    DOI: 10.1126/science.aao2469

    Link: http://science.sciencemag.org/content/360/6395/1342

    Testing General Relativity on galaxy scales

    Einstein's theory of gravity, General Relativity (GR), has been tested precisely within the Solar System. However, it has been difficult to test GR on the scale of an individual galaxy. Collett et al. exploited a nearby gravitational lens system, in which light from a distant galaxy (the source) is bent by a foreground galaxy (the lens). Mass distribution in the lens was compared with the curvature of space-time around the lens, independently determined from the distorted image of the source. The result supports GR and eliminates some alternative theories of gravity.

    Abstract

    Einstein’s theory of gravity, General Relativity, has been precisely tested on Solar System scales, but the long-range nature of gravity is still poorly constrained. The nearby strong gravitational lens ESO 325-G004 provides a laboratory to probe the weak-field regime of gravity and measure the spatial curvature generated per unit mass, γ. By reconstructing the observed light profile of the lensed arcs and the observed spatially resolved stellar kinematics with a single self-consistent model, we conclude that γ = 0.97 ± 0.09 at 68% confidence. Our result is consistent with the prediction of 1 from General Relativity and provides a strong extragalactic constraint on the weak-field metric of gravity.

    [–] Report: World trending to hit 50% renewables, 11% coal by 2050 mvea 1 points ago in Futurology

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    [–] Over one-third of industrial robots purchased last year were installed in China mvea 1 points ago in Futurology

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    [–] Volvo promises self-driving 2021 XC90 you can nap in mvea 1 points ago in Futurology

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    Rule 9 - Avoid posting content that is a duplicate of content posted within the last 2-3 days.

    https://www.reddit.com/r/Futurology/comments/8svxcf/volvo_promises_selfdriving_2021_xc90_you_can_nap/

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    [–] Ketamine acts fast to treat depression and its effects last - New research describes the molecular mechanisms behind ketamine’s ability to squash depression and keep it at bay. The long-lasting effects of ketamine may be due to G proteins, and not solely by blocking the NMDA receptor. mvea 5 points ago in psychology

    The title of the post is a copy and paste from the title, second, seventh and eight paragraphs of the linked academic press release here :

    Ketamine acts fast to treat depression and its effects last — but how?

    Now, researchers led by Mark Rasenick, distinguished professor of physiology and psychiatry in the University of Illinois at Chicago College of Medicine, describe the molecular mechanisms behind ketamine’s ability to squash depression and keep it at bay. They report their findings in the journal Molecular Psychiatry.

    In his current research, Rasenick and his colleagues performed a similar experiment with ketamine and noticed that the G proteins left the rafts much faster. G proteins began migrating out of the lipid rafts within 15 minutes. And the long-lasting effects of ketamine may be due to the fact that the G proteins were very slow to move back into the lipid rafts, Rasenick explained.

    The finding contradicts the long-held idea that ketamine works solely by blocking a cellular receptor called the NMDA receptor, which sits on the surface of nerve cells and helps transmit signals.

    Journal Reference:

    Nathan H. Wray, Jeffrey M. Schappi, Harinder Singh, Nicolas B. Senese, Mark M. Rasenick.

    NMDAR-independent, cAMP-dependent antidepressant actions of ketamine.

    Molecular Psychiatry, 2018;

    DOI: 10.1038/s41380-018-0083-8

    Link: https://www.nature.com/articles/s41380-018-0083-8

    Abstract

    Ketamine produces rapid and robust antidepressant effects in depressed patients within hours of administration, often when traditional antidepressant compounds have failed to alleviate symptoms. We hypothesized that ketamine would translocate Gαs from lipid rafts to non-raft microdomains, similarly to other antidepressants but with a distinct, abbreviated treatment duration. C6 glioma cells were treated with 10 µM ketamine for 15 min, which translocated Gαs from lipid raft domains to non-raft domains. Other NMDA antagonist did not translocate Gαs from lipid raft to non-raft domains. The ketamine-induced Gαs plasma membrane redistribution allows increased functional coupling of Gαs and adenylyl cyclase to increase intracellular cyclic adenosine monophosphate (cAMP). Moreover, increased intracellular cAMP increased phosphorylation of cAMP response element-binding protein (CREB), which, in turn, increased BDNF expression. The ketamine-induced increase in intracellular cAMP persisted after knocking out the NMDA receptor indicating an NMDA receptor-independent effect. Furthermore, 10 µM of the ketamine metabolite (2R,6R)-hydroxynorketamine (HNK) also induced Gαs redistribution and increased cAMP. These results reveal a novel antidepressant mechanism mediated by acute ketamine treatment that may contribute to ketamine’s powerful antidepressant effect. They also suggest that the translocation of Gαs from lipid rafts is a reliable hallmark of antidepressant action that might be exploited for diagnosis or drug development.

    [–] Ketamine acts fast to treat depression and its effects last - New research describes the molecular mechanisms behind ketamine’s ability to squash depression and keep it at bay. The long-lasting effects of ketamine may be due to G proteins, and not solely by blocking the NMDA receptor. mvea 1 points ago in Futurology

    The title of the post is a copy and paste from the title, second, seventh and eight paragraphs of the linked academic press release here :

    Ketamine acts fast to treat depression and its effects last — but how?

    Now, researchers led by Mark Rasenick, distinguished professor of physiology and psychiatry in the University of Illinois at Chicago College of Medicine, describe the molecular mechanisms behind ketamine’s ability to squash depression and keep it at bay. They report their findings in the journal Molecular Psychiatry.

    In his current research, Rasenick and his colleagues performed a similar experiment with ketamine and noticed that the G proteins left the rafts much faster. G proteins began migrating out of the lipid rafts within 15 minutes. And the long-lasting effects of ketamine may be due to the fact that the G proteins were very slow to move back into the lipid rafts, Rasenick explained.

    The finding contradicts the long-held idea that ketamine works solely by blocking a cellular receptor called the NMDA receptor, which sits on the surface of nerve cells and helps transmit signals.

    Journal Reference:

    Nathan H. Wray, Jeffrey M. Schappi, Harinder Singh, Nicolas B. Senese, Mark M. Rasenick.

    NMDAR-independent, cAMP-dependent antidepressant actions of ketamine.

    Molecular Psychiatry, 2018;

    DOI: 10.1038/s41380-018-0083-8

    Link: https://www.nature.com/articles/s41380-018-0083-8

    Abstract

    Ketamine produces rapid and robust antidepressant effects in depressed patients within hours of administration, often when traditional antidepressant compounds have failed to alleviate symptoms. We hypothesized that ketamine would translocate Gαs from lipid rafts to non-raft microdomains, similarly to other antidepressants but with a distinct, abbreviated treatment duration. C6 glioma cells were treated with 10 µM ketamine for 15 min, which translocated Gαs from lipid raft domains to non-raft domains. Other NMDA antagonist did not translocate Gαs from lipid raft to non-raft domains. The ketamine-induced Gαs plasma membrane redistribution allows increased functional coupling of Gαs and adenylyl cyclase to increase intracellular cyclic adenosine monophosphate (cAMP). Moreover, increased intracellular cAMP increased phosphorylation of cAMP response element-binding protein (CREB), which, in turn, increased BDNF expression. The ketamine-induced increase in intracellular cAMP persisted after knocking out the NMDA receptor indicating an NMDA receptor-independent effect. Furthermore, 10 µM of the ketamine metabolite (2R,6R)-hydroxynorketamine (HNK) also induced Gαs redistribution and increased cAMP. These results reveal a novel antidepressant mechanism mediated by acute ketamine treatment that may contribute to ketamine’s powerful antidepressant effect. They also suggest that the translocation of Gαs from lipid rafts is a reliable hallmark of antidepressant action that might be exploited for diagnosis or drug development.