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In recent years, physicists have been trying to better understand the behavior of individual quantum particles as they move in space. Yet directly imaging these particles with high precision has so far proved challenging, due to the limitations of existing microscopy methods.

Researchers at CNRS and École Normale Supérieure in Paris, France, have now developed a new protocol to directly image the evolution of a single-atom wave packet, a delocalized quantum state that determines the probability that an associated atom will be found in a specific location. This imaging technique, introduced in Physical Review Letters, could open exciting possibilities for the precise study of complex quantum systems in continuous space.

“Our group is interested in the study of ultracold atoms, the coldest systems in the universe, just a few billionths of degrees above absolute zero, where matter displays fascinating behaviors,” Tarik Yefsah, senior author of the paper, told Phys.org. “One of these behaviors is the so-called superfluidity, a remarkable state of matter, where particles flow without friction.

In an amazing achievement akin to adding solar panels to your body, a northeast sea slug sucks raw materials from algae to provide its lifetime supply of solar-powered energy, according to a study by Rutgers University–New Brunswick and other scientists.

“It’s a remarkable feat because it’s highly unusual for an animal to behave like a plant and survive solely on photosynthesis,” said Debashish Bhattacharya, senior author of the study and distinguished professor in the Department of Biochemistry and Microbiology at Rutgers–New Brunswick. “The broader implication is in the field of artificial photosynthesis. That is, if we can figure out how the slug maintains stolen, isolated plastids to fix carbon without the plant nucleus, then maybe we can also harness isolated plastids for eternity as green machines to create bioproducts or energy. The existing paradigm is that to make green energy, we need the plant or alga to run the photosynthetic organelle, but the slug shows us that this does not have to be the case.”

The sea slug Elysia chlorotica, a mollusk that can grow to more than two inches long, has been found in the intertidal zone between Nova Scotia, Canada, and Martha’s Vineyard, Massachusetts, as well as in Florida. Juvenile sea slugs eat the nontoxic brown alga Vaucheria litorea and become photosynthetic – or solar-powered – after stealing millions of algal plastids, which are like tiny solar panels, and storing them in their gut lining, according to the study published online in the journal Molecular Biology and Evolution.

Using the James Webb Space Telescope (JWST), astronomers have observed enigmatic rings in the planetary nebula NGC 1,514, visible in the mid-infrared band. Results of the new observations, published Feb. 28 on the arXiv pre-print server, shed more light on the properties and nature of these rings.

Planetary nebulae (PNe) are expanding shells of gas and dust that have been ejected from a star during the process of its evolution from a into a red giant or white dwarf. They are relatively rare, but are important for astronomers studying the chemical evolution of stars and galaxies.

NGC 1,514 (also known as Crystal Ball Nebula) is a large and complex elliptical planetary at a distance of about 1,500 light years away. It originated from a designated HD 281679. The bright, visible component of the system is a giant star of spectral type A0III, while the nebula-generating companion is now a hot, sub-luminous O-type star.

Today Dr. Dan Korman and Noah McKay join me to discuss evolutionary debunking arguments. Can our moral beliefs survive skeptical threats?

Like the show? Help it grow! Consider becoming a patron (thanks!): / majestyofreason.

If you wanna make a one-time donation or tip (thanks!): https://www.paypal.com/paypalme/josep… 0:00 Intro 1:40 Debunking arguments 6:22 Three kinds of debunking arguments 14:43 Telic debunking argument 22:05 Explanationist pushback 38:51 Swampman pushback 59:51 New function pushback 1:16:45 Dan’s favored approach 1:25:01 Concluding thoughts RESOURCES Dan’s website (with his papers): https://danielzkorman.weebly.com/ Noah’s website (with his papers): https://noahdmckay.wordpress.com/ Dan’s paper, “Debunking Arguments”, https://philarchive.org/archive/KORDA-2 Dan’s paper, “An explanationist Account of Genealogical Defeat ”, https://philpapers.org/rec/KORAEA-4 Noah’s paper, ” Can Rational Reflection Save Moral Knowledge from Debunking?”, https://philpapers.org/rec/MCKCRR Noah’s paper, ” Moral knowledge and the existence of God”, https://philpapers.org/rec/MCKMKA My Metaethics playlist: • Metaethics My Springer book: (a) https://www.amazon.com/Existential-In?tag=lifeboatfound-20… (b) https://link.springer.com/book/10.100… THE USUAL… Follow the Majesty of Reason podcast! https://open.spotify.com/show/4Nda5uN… Join the Discord and chat all things philosophy! https://dsc.gg/majestyofreason My website: https://josephschmid.com My PhilPeople profile: https://philpeople.org/profiles/josep

OUTLINE

0:00 Intro.
1:40 Debunking arguments.
6:22 Three kinds of debunking arguments.
14:43 Telic debunking argument.
22:05 Explanationist pushback.
38:51 Swampman pushback.
59:51 New function pushback.
1:16:45 Dan’s favored approach.
1:25:01 Concluding thoughts.

RESOURCES.

A study of artificial human and chimpanzee nerve cells revealed how faster-evolving DNA enables neurons to develop increasingly complex brain power.

How did humans evolve brains capable of complex language, civilization, and more?

The answer may lie in exceptional DNA. Scientists at UC San Francisco discovered that certain regions of our chromosomes have evolved at remarkable speeds, giving us an advantage in brain development over apes. However, this rapid evolution may also make us more susceptible to uniquely human brain disorders.

A new source of nitrogen has been discovered. Researchers from RPTU University Kaiserslautern-Landau in southwestern Germany are unraveling the mysteries of a bygone era. As part of ongoing studies, they are investigating how life could have developed on early Earth. Contrary to previous assumptions, biologically available nitrogen does not appear to have been a limiting factor.

Astronomers have performed a multiwavelength study of nine open cluster candidates. As a result, they found that all of them are genuine open clusters and characterized by their fundamental properties. The finding was reported in a research paper published Feb. 21 on the arXiv pre-print server.

Open clusters (OCs), formed from the same giant molecular cloud, are groups of stars loosely gravitationally bound to each other. So far, more than 1,000 of them have been discovered in the Milky Way, and scientists are still looking for more, hoping to find a variety of these stellar groupings.

Expanding the list of known and studying them in detail could be crucial for improving our understanding of the formation and evolution of our galaxy.

The results show two distinct patterns in the protective effect of natural infection against reinfection in the Omicron era compared to the pre-Omicron era. Before the emergence of Omicron, natural infection offered robust protection against reinfection, with roughly 80% effectiveness and minimal signs of waning over time after the infection. However, during the Omicron era, this protection was strong only for recently infected individuals, rapidly declining over time after the infection and ultimately diminishing within a year. These patterns were consistent regardless of whether any infection or only symptomatic infection was considered as an outcome, and for both vaccinated and unvaccinated populations.

The two distinct patterns observed in the Omicron versus pre-Omicron eras provide population-level results that validate previous experimental molecular evidence1,2,18,19,20, and are probably the result of a complex interplay of several interrelated factors, in addition to waning immunity, immune evasion and the accelerated and convergent evolution of Omicron, such as immune imprinting, varying immunogenicity, global population immunity faced by the strains and population characteristics associated with infections at different stages of the pandemic.

Whereas these factors are interconnected and challenging to disentangle, the observed differences in protection against reinfection may stem from distinct evolutionary pressures acting on SARS-CoV-2 during the pre-Omicron and Omicron eras. In the pre-Omicron era, with a large proportion of individuals remaining immune naive because of non-pharmaceutical interventions and delayed scale-up of vaccination, intrinsic transmissibility may have been the primary driver of viral adaptation. This was evidenced by the emergence of more transmissible variants such as Alpha4,22,23 and Delta24,25. Conversely, following the very large and widespread Omicron wave in early 2022 (Extended Data Fig. 3)26, most individuals possessed some level of immunity, either from infection or vaccination. This may have shifted the dominant evolutionary pressure towards immune escape through not only antigenic drift, but also recombination and convergent evolution as the adaptive mechanisms for the virus2,18,27,28.