(Image Caption: The Synapses Of Pyramid Cells In The Cerebral Cortex Form Functional Groups. Some Of

Today is World Anaesthesia Day! Here’s a look at the chemistry behind a range of anaesthetics. More info here and here.

Most cones don’t really see color

We see color because of specialized light-sensing cells in our eyes called cones. One type, L-cones, sees the reds of strawberries and fire trucks; M-cones detect green leaves, and S-cones let us know the sky is blue. But vision scientists have now discovered that not all cones sense color (see video). The finding was made possible because, for the first time, scientists were able to look at individual photo-sensing cells.

DNA from the deep? Antikythera shipwreck yields ancient human bones

Death, when it came, was sudden and cruel. The individual, either a crew member or passenger, was trapped on board when the huge ship foundered. Dashed on the rocks, the vessel slid beneath the waves, tumbled down an undersea cliff, and swiftly became buried in sediment on the seabed.

Now, more than 2,000 years later, archaeologists have recovered the bones of the individual they now call Pamphilos. Thought to be a man in his late teens to early 20s, he was on the ship sailing from Asia Minor to Rome when disaster struck off the tiny Greek island of Antikythera between Crete and the Peloponnese.

Swarms of magnetic bacteria could be used to deliver drugs to tumors 

Researchers funded in part by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) have recently shown that magnetic bacteria are a promising vehicle for more efficiently delivering tumor-fighting drugs. They reported their results in the August 2016 issue of Nature Nanotechnology.

Ouajdi Felfoul, Mahmood Mohammadi, Samira Taherkhani, Dominic de Lanauze, Yong Zhong Xu, Dumitru Loghin, Sherief Essa, Sylwia Jancik, Daniel Houle, Michel Lafleur, Louis Gaboury, Maryam Tabrizian, Neila Kaou, Michael Atkin, Té Vuong, Gerald Batist, Nicole Beauchemin, Danuta Radzioch, Sylvain Martel. Magneto-aerotactic bacteria deliver drug-containing nanoliposomes to tumour hypoxic regions. Nature Nanotechnology, 2016; DOI: 10.1038/nnano.2016.137

Illustration showing magnetic bacteria delivering drugs to a tumor. Credit: NanoRobotics Laboratory, Polytechnique Montreal

CRISPR in Animals- Simplified. CRISPR is a breakthrough that makes genetic editing easier than ever before. How does it work, and what can it do? You can learn the basics in under 5 minutes from this animation.

Neural Pathways by Alexey Kashpersky

Memory Competition

Most of the brain contains cells that no longer divide and renew. However, the dentate gyrus, nestled within the memory-forming centre of the brain (the hippocampus) is one of the few sites where new cells continue to form throughout life. As a person ages, there is an ever-increasing struggle for these new dentate gyrus neurons (coloured pink) to integrate with existing older neurons (green) because the latter already has well-established connections. This may be why learning and memorisation becomes more difficult as a person gets older. Scientists have now found that by temporarily reducing the number of dendritic spines – branches of neurons that form connections with other neurons – in the mature cells, the new cells have a better chance of functionally integrating. Indeed, in live mice, briefly eliminating dendritic spines boosted the number of integrated new neurons, which rejuvenated the hippocampus and improved the animals’ memory precision.

Written by Ruth Williams

Image courtesy of Kathleen McAvoy

Center for Regenerative Medicine, Massachusetts General Hospital, Boston, MA, USA

Copyright held by original authors

Research published in Neuron, September 2016

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Superconducting Bismuth Is Real, and It's Forcing Us to Rethink the Nature of Superconductivity

A Nobel Prize-winning theory has been challenged.

Bismuth is one of the weirdest-looking elements on the Periodic Table, but its internal properties just got even stranger. Scientists have discovered that at a fraction of a degree above absolute zero (-273.15°C), bismuth becomes a superconductor - a material that can conduct electricity without resistance.

According to the current theory of superconductivity, that doesn’t make a whole lot of sense, because for 40 years now, scientists have assumed that superconducting materials must be abundant in free-flowing mobile electrons. But in bismuth, there’s just one mobile electron for every 100,000 atoms.

“In general, compounds that exhibit superconductivity have roughly one mobile electron per atom,” Srinivasan Ramakrishnan from the Tata Institute of Fundamental Research in India explained to Chemistry World.

“However, in bismuth, one mobile electron is shared by 100,000 atoms – since [the] carrier density is so small, people did not believe bismuth will superconduct.”

Continue Reading.

Crystals of the female hormone oxytocin

In women this hormone is secreted naturally by the pituitary gland. Oxytocin causes contractions of the uterus during labour, and it also stimulates the flow of milk in women who are breast-feeding.