MI weekly selection #14
3-body problem gets 13 more possible solutions
Scientists have come up with 13 new solutions to the “three-body problem,” a situation in which three objects orbit each other in a pattern. The discoveries, which will help astrophysicists further understand planetary systems, brings the total number of solutions to 16.
Milovan Šuvakov, V. Dmitrašinović Three Classes of Newtonian Three-Body Planar Periodic Orbits arXiv: 1303,0181
Electrical brain stimulation speeds learning, with a price
Electrical signals used to stimulate the brain may improve learning and other functions, but could also adversely affect cognitive thinking, according to a study. The experiment looked at how transcranial electrical stimulation — which has been showed to double a person’s learning speed — affected a person’s ability to automatically perform tasks. Those who received TES showed signs of learning faster, but also failed at automatically performing tasks.
Teresa Iuculano & Roi Cohen Kadosh (2013) The Mental Cost of Cognitive Enhancement The Journal of Neuroscience, 33(10): 4482-4486; DOI: 10.1523/JNEUROSCI.4927-12.
Antibiotics play key role in fighting malnutrition
Treating malnutrition with antibiotics in addition to food could help prevent fewer children from dying, according to two studies. The first study found that antibiotics given within the first seven days of treatment helped prevent more deaths, though there was little effect on how quickly they recovered. The second study found that children suffering from kwashiorkor, a type of malnutrition, had microbes in their gut that did not change with food alone. Scientists warn, however, that there are risks to widespread use of antibiotics and that a holistic treatment to malnutrition needs to be considered.
Indi Trehan, Hayley S. Goldbach, Lacey N. LaGrone, Guthrie J. Meuli, Richard J. Wang, Kenneth M. Maleta, and Mark J. Manary. (2013) Antibiotics as Part of the Management of Severe Acute Malnutrition New England Journal of Medicine DOI: 10.1056/NEJMoa1202851
Smith MI, Yatsunenko T, Manary MJ, Trehan I, Mkakosya R, Cheng J, Kau AL, Rich SS, Concannon P, Mychaleckyj JC, Liu J, Houpt E, Li JV, Holmes E,Nicholson J, Knights D, Ursell LK, Knight R, Gordon JI. (2013) Gut microbiomes of Malawian twin pairs discordant for kwashiorkor. DOI: 10.1126/science.1229000
Some plants reproduction could be a no-go in outer space
Plant reproduction may be more dependent on gravity than once believed. Scientists used simulated antigravity environments to study how plants might reproduce without the force. They discovered that intercellular transport, which is necessary for mating plants and communicating brain cells in humans, was affected by the lack of gravity.
Chebli Y, Pujol L, Shojaeifard A, Brouwer I, van Loon JJWA, et al. (2013) Cell Wall Assembly and Intracellular Trafficking in Plant Cells Are Directly Affected by Changes in the Magnitude of Gravitational Acceleration. PLoS ONE 8(3): e58246. DOI:10.1371/journal.pone.0058246
Ancient birds used 4 wings in flight
Scientists in China have detailed the fossil specimens of 11 types of four-winged birds. The “basal birds” show evidence of eventually losing the hind-limb wings in favor of the two forelimb wings and birdlike feet, a crucial transition that “may have played an important role in the evolution of flight,” researchers said. While the existence of four-winged birds has been confirmed, the two-dimensional nature of the fossils make it difficult for scientists to explain the aerodynamic function, if any, of having four wings.
Xiaoting Zheng, Zhonghe Zhou, Xiaoli Wang, Fucheng Zhang, Xiaomei Zhang, Yan Wang, Guangjin Wei1, Shuo Wang, Xing Xu (2013) Hind Wings in Basal Birds and the Evolution of Leg Feathers Science DOI: 10.1126/science.1228753