Archive for the ‘evolution’ category: Page 7

Mar 9, 2024

Astronomers Observe the Effect of Dark Matter on the Evolution of the Galaxies

Posted by in categories: cosmology, evolution

Dark matter comprises around 85% of all the matter in the universe. Although ordinary matter absorbs, reflects and emits light, dark matter cannot be seen directly, which makes its detection difficult. Its existence is inferred from its gravitational effects on visible matter, the material that forms stars, planets, and other objects in the cosmos.

Galaxies are made up of these two types of material The dark matter is distributed in halos, which are huge structures surrounding galaxies, while the ordinary matter is mainly present in the central regions where most of the stars are found.

Traditionally observational studies of galactic evolution have centered on the role of ordinary matter, even though it is quite a small fraction of the mass of a galaxy. For decades there have been theoretical predictions about the effect that dark matter should have on the evolution of galaxies. However, in spite of numerous efforts, there is no clear consensus about this.

Mar 9, 2024

An evolutionary mystery 125 million years in the making

Posted by in categories: bioengineering, biotech/medical, evolution, genetics

Plant genomics has come a long way since Cold Spring Harbor Laboratory (CSHL) helped sequence the first plant genome. But engineering the perfect crop is still, in many ways, a game of chance. Making the same DNA mutation in two different plants doesn’t always give us the crop traits we want. The question is why not? CSHL plant biologists just dug up a reason.

CSHL Professor and HHMI Investigator Zachary Lippman and his team discovered that tomato and Arabidopsis thaliana plants can use very different regulatory systems to control the same exact gene. Incredibly, they linked this behavior to extreme genetic makeovers that occurred over 125 million years of evolution.

The scientists used genome editing to create over 70 mutant strains of tomato and Arabidopsis thaliana plants. Each mutation deleted a piece of regulatory DNA around a gene known as CLV3. They then analyzed the effect each mutation had on and development. When the DNA keeping CLV3 in check was mutated too much, fruit growth exploded. They published their findings in PLoS Genetics.

Mar 9, 2024

Assembly Theory: Bold New ‘Theory of Everything’ Could Unite Physics And Evolution

Posted by in categories: biotech/medical, engineering, evolution, quantum physics

A recent study conducted at Tel Aviv University has devised a large mechanical system that operates under dynamical rules akin to those found in quantum systems. The dynamics of quantum systems, composed of microscopic particles like atoms or electrons, are notoriously difficult, if not impossible, to observe directly.

However, this new system allows researchers to visualize occurring in specialized “topological” materials through the movement of a system of coupled pendula.

The research is a collaboration between Dr. Izhar Neder of the Soreq Nuclear Research Center, Chaviva Sirote-Katz of the Department of Biomedical Engineering, Dr. Meital Geva and Prof. Yair Shokef of the School of Mechanical Engineering, and Prof. Yoav Lahini and Prof. Roni Ilan of the School of Physics and Astronomy at Tel Aviv University and was recently published in the Proceedings of the National Academy of Sciences.

Mar 9, 2024

Harvard Scientists Say New Research “Sets the Stage” For Helping Humans Regrow Lost Limbs

Posted by in categories: biotech/medical, evolution

In a collaboration with Kyushu University, a team of Harvard University scientists says their new research into the ability to regrow lost limbs sets the stage’ for proper limb regeneration.

Of course, some animals, including amphibians, can regrow a lost arm or leg, but the team behind this latest research hopes to bring that ability to humans who hope to regrow lost limbs.

The researchers also say this process could facilitate the growing of limbs in animals that lost them to evolution, such as snakes.

Mar 8, 2024

Unveiling the Binding Mechanisms of Cancer-Promoting Proteins

Posted by in categories: biotech/medical, evolution

The Melanoma Antigen Gene (MAGE) family consists of more than 40 proteins in humans, most of which are only present in the testes under healthy conditions. However, in many cancers, these proteins are found in high levels in tissues where they are not usually expressed and are believed to play a role in promoting cancer progression. Researchers from the Bhogaraju group at the European Molecular Biology Laboratory (EMBL) Grenoble have gained new insights into how these proteins bind their targets. The findings could potentially aid in the development of drugs against chemotherapy-or radiotherapy-resistant cancers.

The findings are published in The EMBO Journal, in an article titled, “Structural basis for RAD18 regulation by MAGEA4 and its implications for RING ubiquitin ligase binding by MAGE family proteins.”

“MAGEA4 is a cancer-testis antigen primarily expressed in the testes but aberrantly overexpressed in several cancers,” the researchers wrote. “MAGEA4 interacts with the RING ubiquitin ligase RAD18 and activates translesion DNA synthesis (TLS), potentially favoring tumor evolution. Here, we employed NMR and AlphaFold2 (AF) to elucidate the interaction mode between RAD18 and MAGEA4, and reveal that the RAD6-binding domain (R6BD) of RAD18 occupies a groove in the C-terminal winged-helix subdomain of MAGEA4.”

Mar 5, 2024

What shape is the universe?

Posted by in categories: evolution, space

Key Takeaways:

Princeton University cosmologist David Spergel emphasizes that the universe’s shape reveals crucial insights into its historical evolution and future trajectory. Questions regarding whether the universe will expand indefinitely or eventually contract, as well as its finiteness or infiniteness, all pivot on its shape.

Mar 2, 2024

Dialogues In Longevity — Dr. Aubrey de Grey & Dr. Michael Rose — Past, Present & Future Of Longevity

Posted by in categories: evolution, life extension

Dialogues In Longevity With Dr. Aubrey de Grey, President & Chief Science Officer, Longevity Escape Velocity Foundation & Dr. Michael Rose, Director of the Network for Experimental Research on Evolution (NERE), and Professor, Department of Ecology and Evolutionary Biology, University of…

Mar 1, 2024

Inflation and Bounce from Classical and Loop Quantum Cosmology Imperfect Fluids

Posted by in categories: cosmology, evolution, information science, quantum physics, singularity

The purpose of this work is to investigate how several inflationary and bouncing scenarios can be realized by imperfect fluids. We shall use two different theoretical frameworks, namely classical cosmology and Loop Quantum Cosmology (LQC) (see where the derivation of the Hamiltonian in LQC was firstly derived to yield the modified Friedman equation, and also see for a recent derivation of the effective Hamiltonian in LQC, which was derived by demanding repulsive gravity, as in Loop Quantum Gravity). In both cases we shall investigate which imperfect fluid can realize various inflationary and bouncing cosmology scenarios. The inflationary cosmology and bouncing cosmology are two alternative scenarios for our Universe evolution. In the case of inflation, the Universe starts from an initial singularity and accelerates at early times, while in the case of the bouncing cosmology, the Universe initially contracts until it reaches a minimum radius, and then it expands again. With regards to inflation, we shall be interested in four different inflationary scenarios, namely the intermediate inflation, the Starobinsky inflation, and two constant-roll inflation scenarios. With regards to bouncing cosmologies, we shall be interested in realizing several well studied bouncing cosmologies, and particularly the matter bounce scenario, the superbounce scenario and the singular bounce.

As we already mentioned we shall use two theoretical frameworks, that of classical cosmology and that of LQC. After presenting the reconstruction methods for realizing the various cosmologies with imperfect fluids, we proceed to the realization of the cosmologies by using the reconstruction methods. In the case of classical cosmology, we will calculate the power spectrum of primordial curvature perturbations, the scalar-to-tensor ratio and the running of the spectral index for all the aforementioned cosmologies, and we compare the results to the recent Planck data. The main outcome of our work is that, although the cosmological scenarios we study in this paper are viable in other modified gravity frameworks, these are not necessarily viable in all the alternative modified gravity descriptions. As we will demonstrate, in some cases the resulting imperfect fluid cosmologies are not compatible at all with the observational data, and in some other cases, there is partial compatibility.

We need to note that the perturbation aspects in LQC are not transparent enough and assume that there are no non-trivial quantum gravitational modifications arising due to presence of inhomogeneities. As it was shown in, a consistent Hamiltonian framework does not allow this assumption to be true. The perturbations issues that may arise in the context of the present work, are possibly more related to some early works in LQC, so any calculation of the primordial power spectrum should be addressed as we commented above.

Feb 29, 2024

Scientists reveal how first cells could have formed on Earth

Posted by in categories: chemistry, evolution

Roughly 4 billion years ago, Earth was developing conditions suitable for life. Origin-of-life scientists often wonder if the type of chemistry found on the early Earth was similar to what life requires today. They know that spherical collections of fats, called protocells, were the precursor to cells during this emergence of life. But how did simple protocells first arise and diversify to eventually lead to life on Earth?

Now, Scripps Research scientists have discovered one plausible pathway for how protocells may have first formed and chemically progressed to allow for a diversity of functions.

The findings, published online on February 29, 2024, in the journal Chem, suggest that a chemical process called phosphorylation (where are added to the molecule) may have occurred earlier than previously expected. This would lead to more structurally complex, double chained protocells capable of harboring chemical reactions and dividing with a diverse range of functionalities. By revealing how protocells formed, scientists can better understand how could have taken place.

Feb 29, 2024

Alex Rosenberg | Intentionality, Evolution, and More

Posted by in categories: biological, evolution, neuroscience

Alex Rosenberg is the R. Taylor Cole Professor of Philosophy at Duke University. His research focuses on the philosophy of biology and science more generally, mind, and economics.

/ friction.
/ discord.
/ frictionphilo.

Continue reading “Alex Rosenberg | Intentionality, Evolution, and More” »

Page 7 of 134First4567891011Last