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A group of astronomers poring over data from the James Webb Space Telescope (JWST) has glimpsed light from ionized helium in a distant galaxy, which could indicate the presence of the universe’s very first generation of stars.

These long-sought, inaptly named “Population III” stars would have been ginormous balls of hydrogen and helium sculpted from the universe’s primordial gas. Theorists started imagining these first fireballs in the 1970s, hypothesizing that, after short lifetimes, they exploded as supernovas, forging heavier elements and spewing them into the cosmos. That star stuff later gave rise to Population II stars more abundant in heavy elements, then even richer Population I stars like our sun, as well as planets, asteroids, comets and eventually life itself.

When it comes to creating ever more intriguing quantum systems, a constant need is finding new ways to observe them in a wide range of physical scenarios. JILA Fellow Cindy Regal and JILA and NIST Fellow Ana Maria Rey have teamed up with Oriol Romero-Isart from the University of Innsbruck and IQOQI to show that a trapped particle in the form of an atom readily reveals its full quantum state with quite simple ingredients, opening up opportunities for studies of the quantum state of ever larger particles.

In the an atom does not behave as a point particle; instead it behaves more as a wave. Its properties (e.g., its position and velocity) are described in terms of what is referred to as the wavefunction of the atom. One way to learn about the wavefunction of a particle is to let the atom fly and then capture its location with a camera.

And with the right tricks, pictures can be taken of the particle’s quantum state from many vantage points, resulting in what is known as quantum tomography (“tomo” being Greek for slice or section, and “graphy” meaning describing or recording). In the work published in Nature Physics, the authors used a rubidium atom placed carefully in a specific state of its motion in a tightly focused laser beam, known as an optical tweezer. And they were able to observe it from many vantage points by letting it evolve in the optical tweezer in time. Like a ball rolling in a bowl, at different times the velocity and location of the particle interchange, and by snapping pictures at the right time during a video reel of the ball, many vantages of the particle’s state can be revealed.

(http://www.evol-net.fr/index.php?option=com_tlpteam&view=team&id=2&Itemid=559) is a Research Director at the French National Centre for Scientific Research (CNRS), the French state research organization and the largest fundamental science agency in Europe.

Dr. Bapteste has both a Ph.D. in evolutionary biology from Pierre and Marie Curie University and a Ph.D. in the philosophy of biology from Pantheon-Sorbonne University.

Dr. Bapteste is the Co-Director of the Adaptation, Intégration, Réticulation, Evolution (AIRE) team, which develops new methods and new concepts, in particular related to biological networks, in order to study evolution and aging. Specifically, the AIRE team works to enhance the evolutionary theory i) by expanding its scope by targeting additional objects of studies (such as novel units of selection and novel still unknown taxonomical groups from the microbial dark matter, and mobile elements) and ii) by expanding evolutionary studies towards more general models, able to in particular account for chimerism and interactions between biological elements, from molecules to ecosystems.

Dr. Bapteste is the author of 95 scientific articles and 4 books of popular sciences: “Les gènes voyageurs: l’odyssée de l’évolution”, “Conflits intérieurs: fable scientifique”, “Tous entrelacés! Des gènes aux super-organismes, les réseaux de l’évolution”, and “Tout se transforme! Comment marche l’évolution”.

New video: Stephanie Dainow, Executive Director at Lifespan.io / Lifespan Extension Advocacy Foundation, at #RejuvenationStartupSummit 2022.

Stephanie speaks about Lifespan.io advocating for the development of medical technologies to rejuvenate aged tissues and organs.

Enjoy →

For more summit videos and regular updates, visit: youtube.com/user/foreverhealthyorg

Microsoft announced today that it added device isolation support to Microsoft Defender for Endpoint (MDE) on onboarded Linux devices.

Enterprise admins can manually isolate Linux machines enrolled as part of a public preview using the Microsoft 365 Defender portal or via API requests.

Once isolated, threat actors will no longer have a connection to the breached system, cutting off their control and blocking malicious activity like data theft.

What led to the emergence of complex organisms on Earth? It’s a significant unanswered question in biology. Researchers from Christa Schleper’s team at the University of Vienna and Martin Pilhofer’s team at ETH Zurich have taken a step towards resolving it. The scientists succeeded in cultivating a special archaeon and characterizing it more precisely using microscopic methods.

This member of the Asgard archaea exhibits unique cellular characteristics and may represent an evolutionary “missing link” to more complex life forms such as animals and plants. The study was recently published in the journal Nature.

All life forms on earth are divided into three major domains: eukaryotes, bacteria and archaea. Eukaryotes include the groups of animals, plants and fungi. Their cells are usually much larger and, at first glance, more complex than the cells of bacteria and archaea. The genetic material of eukaryotes, for example, is packaged in a cell nucleus and the cells also have a large number of other compartments. Cell shape and transport within the eukaryotic cell are also based on an extensive cytoskeleton. But how did the evolutionary leap to such complex eukaryotic cells come about?

Connectome harmonic decomposition (CHD) generalises the mathematics of the Fourier transform to the network structure of the human brain. The traditional Fourier transform operates in the temporal domain (Fig. 1a): decomposition into temporal harmonics quantifies to what extent the signal varies slowly (low-frequency temporal harmonics) or quickly (high-frequency temporal harmonics) over time (Fig. 1b). Analogously, CHD re-represents a spatial signal in terms of harmonic modes of the human connectome, so that the spatial frequency (granularity) of each connectome harmonic quantifies to what extent the organization of functional brain signals deviates from the organization of the underlying structural network (Fig. 1c, d). Therefore, CHD is fundamentally different from, and complementary to, traditional approaches to functional MRI data analysis. This is because CHD does not view functional brain activity as composed of signals from discrete spatial locations, but rather as composed of contributions from distinct spatial frequencies: each connectome harmonic is a whole-brain pattern with a characteristic spatial scale (granularity)—from an entire hemisphere to just a few millimetres.

On one hand, this means that CHD is unsuitable to address questions pertaining to spatial localisation and the involvement of specific neuroanatomical regions; such questions have been extensively investigated within the traditional framework of viewing brain activity in terms of spatially discrete regions, and several previous studies have implicated specific neuroanatomical regions in supporting consciousness33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49. On the other hand, CHD enables us to consider how brain activity across states of consciousness is shaped by the brain’s distributed network of structural connections, reflecting the contribution of global patterns at different spatial scales—each arising from the network topology of the human connectome. We emphasise that neither approach is inherently superior, but rather they each provide a unique perspective on brain function: one localised, the other distributed.

❤️ Check out Weights & Biases and sign up for a free demo here: https://wandb.com/papers.

📝 The paper “Co-Writing Screenplays and Theatre Scripts with Language Models: An Evaluation by Industry Professionals” is available here:
https://deepmind.github.io/dramatron/details.html.

My latest paper on simulations that look almost like reality is available for free here:
https://rdcu.be/cWPfD

Or this is the orig. Nature Physics link with clickable citations: