Lifeboat Foundation

Here we show that DS2 is an online, synchronous population event accompanied by widespread increases in neural activity and brief arousalions. On the basis of the stationary activation of place cells with fields close to the mouse’s current location, we propose that DS2 may serve as a mechanism to regularly ground the hippocampal representation of position in an environment during immobility. Rapidly switching between current (DS2) and remote (SPW-R) locations would enable cognitive flexibility that varies with sudden changes in the animal’s internal state or changes in the environment (for example, a startling noise). Synchronous neural activity during DS2 may provide opportunity windows for synaptic plasticity, consistent with our findings linking DS2 to associative memory formation.

At the microcircuit level, distinct brain states are shaped by the non-uniform recruitment of local inhibitory cells, which are key for directing information flow²⁷. As arousal-activated AACs heterogeneously innervate principal cells^19,20 and are highly active during DS2 but mostly silent during SPW-Rs, this GABAergic cell (and probably others, such as TORO cells) may be important in regulating the distinct ensemble activity between DS2 and SPW-Rs. At a network level, DS2 is thought to be primarily triggered by the medial entorhinal cortex, which contains neurons that encode self-referenced movement variables, locations and environmental borders^28,29,30. This self-referenced spatial input may indeed be key for recruiting spatially tuned hippocampal cells corresponding to an animal’s current position during DS2. Both tones and air puffs reliably evoked DS2 and promoted current position encoding, but the identity of the stimulus (tone versus puff) could not be reliably decoded.

In the past 10 years, gene-editing and organoid culture have completely changed the process of biology. Congenital nervous system malformations are difficult to study due to their polygenic pathogenicity, the complexity of cellular and neural regions of the brain, and the dysregulation of specific neurodevelopmental processes in humans. Therefore, the combined application of CRISPR-Cas9 in organoid models may provide a technical platform for studying organ development and congenital diseases. Here, we first summarize the occurrence of congenital neurological malformations and discuss the different modeling methods of congenital nervous system malformations. After that, it focuses on using organoid to model congenital nervous system malformations. Then we summarized the application of CRISPR-Cas9 in the organoid platform to study the pathogenesis and treatment strategies of congenital nervous system malformations and finally looked forward to the future.

Keywords: organoid, CRISPR-Cas9, congenital nervous system malformation, central nervous system, 3D

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Brain organoids have become increasingly used systems allowing 3D-modeling of human brain development, evolution, and disease. To be able to make full use of these modeling systems, researchers have developed a growing toolkit of genetic modification techniques. These techniques can be applied to mature brain organoids or to the preceding embryoid bodies (EBs) and founding cells. This review will describe techniques used for transient and stable genetic modification of brain organoids and discuss their current use and respective advantages and disadvantages. Transient approaches include adeno-associated virus (AAV) and electroporation-based techniques, whereas stable genetic modification approaches make use of lentivirus (including viral stamping), transposon and CRISPR/Cas9 systems. Finally, an outlook as to likely future developments and applications regarding genetic modifications of brain organoids will be presented.

The development of brain organoids (Kadoshima et al., 2013; Lancaster et al., 2013) has opened up new ways to study brain development and evolution as well as neurodevelopmental disorders. Brain organoids are multicellular 3D structures that mimic certain aspects of the cytoarchitecture and cell-type composition of certain brain regions over a particular developmental time window (Heide et al., 2018). These structures are generated by differentiation of induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs) into embryoid bodies followed by, or combined, with neural induction (Kadoshima et al., 2013; Lancaster et al., 2013). In principle, two different classes of brain organoid protocols can be distinguished, namely: (i) the self-patterning protocols which produce whole-brain organoids; and (ii) the pre-patterning protocols which produce brain region-specific organoids (Heide et al., 2018).

It is with sadness — and deep appreciation of my friend and colleague — that I must report the passing of Vernor Vinge.

The technological singularity —or simply the singularity^[1] —is a hypothetical future point in time at which technological growth becomes uncontrollable and irreversible, resulting in unforeseeable consequences for human civilization.^[2][3] According to the most popular version of the singularity hypothesis, I. J. Good’s intelligence explosion model, an upgradable intelligent agent will eventually enter a “runaway reaction” of self-improvement cycles, each new and more intelligent generation appearing more and more rapidly, causing an “explosion” in intelligence and resulting in a powerful superintelligence that qualitatively far surpasses all human intelligence.^[4]

Continue reading “Technological singularity” »

The good news is that a new company has developed an AI inner monologue, the bad news is this makes it significantly smarter.

Advances in oil and gas drilling have cut costs for a form of clean power that could help replace fossil fuels, according to the Department of Energy.

Now the agency is going all in on geothermal energy, which uses heat from deep within the Earth to produce largely pollution-free electricity.

“Gigantic aluminum spiders” might sound like the stuff of nightmares or an antagonist in an anime series. However, for one Norwegian company, they could be the future of the wind energy industry.

WindSpider, a tech company that focuses on onshore and offshore wind turbines, has developed a new self-erecting crane system that could revolutionize the way turbines are built.

Continue reading “Company develops revolutionary technology that allows wind turbines to practically build themselves: ‘It will be a gamechanger’” »

The first patient of Elon Musk’s Neuralink has been presented to the public. Noland Arbaugh had all but given up playing Civilization VI ever since a diving accident dislocated two vertebrae in his cervical spinal cord, leaving him paralyzed from the shoulders down.

When confined to his wheel chair, the 29-year-old American is totally dependent on the care of his parents, who need to shift his weight ever few hours to avoid pressure sores from sitting too long in the same position.

Moving a cursor on a display furthermore required the use of a mouth stick, a specialized assistive device used by quadriplegics.

Open any astronomy textbook to the section on white dwarf stars and you’ll likely learn that they are “dead stars” that continuously cool down over time. New research published in Nature is challenging this theory, with the University of Victoria (UVic) and its partners using data from the European Space Agency’s Gaia satellite to reveal why a population of white dwarf stars stopped cooling for more than eight billion years.

“We discovered the classical picture of all white dwarfs being dead stars is incomplete,” says Simon Blouin, co-principal investigator and Canadian Institute of Theoretical Astrophysics National Fellow at UVic.

“For these white dwarfs to stop cooling, they must have some way of generating extra energy. We weren’t sure how this was happening, but now we have an explanation for the phenomenon.”