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Archive for the ‘evolution’ category: Page 113

Dec 16, 2019

Physicist proposes a new approach in modeling the evolution of the universe

Posted by in categories: cosmology, evolution

A physicist from RUDN University has proposed a new theoretical model for the interaction of spinor and gravitational fields. He considered the evolution of the universe within one of the variants of the widespread Bianchi cosmological model. In this case, a change in the calculated field parameters led to changes in the evolution of the universe under consideration. Upon reaching certain values, it began to shrink down to the Big Bang. The article was published in the journal The European Physical Journal Plus.

The spinor field is characterized by its behavior in interaction with gravitational fields. Dr. Bijan Saha of RUDN University focused on the study of a nonlinear spinor field. With its help, he explained the accelerated expansion of the universe. The study of a spinor field with a non-minimal coupling made it possible to describe not only the expansion of the universe, but also its subsequent contraction and the resulting Big Bang within the framework of the standard Bianchi .

The basic calculations performed by Bijan Saha allow moving away from the isotropic of the Friedman-Robertson-Walker universe (FRW) that is most often used. According to this traditional model, the properties of the universe are independent of the direction in which they are considered. The physicist has put forward an alternative: an anisotropic model in which such dependence exists. On the one hand, the “classical” isotropic model describes the of the modern universe with great precision. On the other hand, there are theoretical arguments and that lead to the conclusion that an anisotropic phase existed in the distant past.

Dec 11, 2019

CRISPR-resistant viruses build ‘safe rooms’ to shield genomes from DNA-dicing enzymes

Posted by in categories: biotech/medical, evolution

Bacteria and the viruses that infect them are engaged in a molecular arms race as ancient as life itself. Evolution has equipped bacteria with an arsenal of immune enzymes, including CRISPR-Cas systems, that target and destroy viral DNA. But bacteria-killing viruses, also known as phages, have devised their own tools to help them outmaneuver even the most formidable of these bacterial defenses.

Now, scientists at UC San Francisco and UC San Diego have discovered a remarkable new strategy that some phages employ to avoid becoming the next casualty of these DNA-dicing enzymes: after they infect , these phages construct an impenetrable “safe room” inside of their host, which protects vulnerable phage DNA from antiviral enzymes. This compartment, which resembles a , is the most effective CRISPR shield ever discovered in viruses.

“In our experiments, these phages didn’t succumb to any of the DNA-targeting CRISPR systems they were challenged with. This is the first time that anyone has found phages that exhibit this level of pan-CRISPR resistance,” said Joseph Bondy-Denomy, Ph.D., assistant professor in the Department of Microbiology and Immunology at UCSF. Bondy-Denomy led the research team that made the discovery, which is detailed in a paper published Dec. 9, 2019 in the journal Nature.

Dec 11, 2019

Astrobiology And The Search For Extraterrestrial Like Life

Posted by in categories: alien life, chemistry, evolution, health

Ira Pastor, ideaXme exponential health ambassador, interviews Dr. Penelope “Penny” Boston, recent Director of NASA’s Astrobiology Institute.

Astrobiology is an interdisciplinary scientific field concerned with the origins, early evolution, distribution, and future of life in the universe, and considers the big question of whether extraterrestrial life exists, and if it does, how humans can detect it.

Continue reading “Astrobiology And The Search For Extraterrestrial Like Life” »

Dec 10, 2019

AstroBiology and the Search for ExtraTerrestrial-Like Life!! — ideaXme — Dr. Penelope “Penny” Boston, PhD., Director of NASA’s Astrobiology Institute — Ira Pastor

Posted by in categories: alien life, astronomy, bioengineering, chemistry, DNA, Elon Musk, evolution, futurism, government, Mark Zuckerberg

Dec 3, 2019

We may finally know the answer to the biggest question, what happened before the Big Bang?

Posted by in categories: cosmology, evolution

The current Lambda CDM model may explain a great deal about the evolution and the chronology of the events that occurred in our Universe but it doesn’t paint the complete picture.

We know of the cosmic inflation that happened followed by the Big Bang itself however how these two are coherently connected has so far defied all our attempts to explain.

During the inflationary period, within less than a trillionth of a second, our universe grew from an infinitesimal point to an octillion (that’s 1 followed by 27 zeroes) times in size, which was followed by a more conventional and gradual period of expansion, nevertheless violent by our standards, which we know as the Big Bang.

Nov 28, 2019

Studies Show that Breast Milk Grows Premature Infant Brains Faster than Formula

Posted by in categories: biotech/medical, evolution, food, neuroscience

It’s easy to get excited about breast milk. Just the basic fact that a woman can eat food and turn it into a complete food instantly tailored to grow that particular newborn is quite outstanding. But there is more to breast milk than what meets the eye and understanding the perfection of it could mean a better life for premature babies.

For starters, when a baby suckles her mama’s breast, a vacuum is created. That’s right. Saliva in, milk out. The infant’s saliva is sucked back into the mother’s nipple, where receptors in her mammary gland read its signals. Katie Hinde, a biologist and associate professor at the Center for Evolution and Medicine at the School of Human Evolution & Social Change at Arizona State University, calls this “baby spit backwash,” and it contains information about the baby’s immune status. As far as scientists can tell, baby spit backwash is one of the ways that breast milk adjusts its immunological composition. When mammary gland receptors detect the presence of pathogens, the mother’s body produces antibodies to fight it, and those antibodies travel through breast milk back into the baby’s body, where they target the infection.

“[Breast] Milk is so incredibly dynamic,” says Hinde. “There are hormones in breast milk, and they reflect the hormones in the mother’s circulation. The ones that help facilitate sleep or waking up are present in your milk. And day milk is going to have a completely different hormonal milieu than night milk.” That broken-down means that breastmilk made at night contains hormones that help your baby sleep.

Nov 21, 2019

Fossils Of Prehistoric Legged Snake Explain The Evolution Slithering Reptiles

Posted by in category: evolution

Due to a lack of fossil records, the early evolution of snakes has been a mystery, until now. Paleontologists have discovered new fossils of the prehistoric legged snake, Najash that has helped solve the mystery of how this creepy-crawly evolved into the slithering reptile it is today.

Researchers have examined the fossils of Najash rionegrina, a rear-limbed snake from the Late Cretaceous period. it has been named after the Biblical legged snake, Nahash, who tempted Eve and Adam to eat the forbidden fruit in the Book of Genesis. Found in Patagonia, Argentina, the fossil has revealed that snakes not only had limbs 100 million years ago but also had cheekbones (jugal bone).

The study published in Science Advances reveals how snakes evolved from their lizard ancestors. Fernando Garberoglio from the Fundación Azara at Universidad Maimónides, Buenos Aires explained, “Our findings support the idea that the ancestors of modern snakes were big-bodied and big-mouthed—instead of small burrowing forms as previously thought.”

Nov 18, 2019

The measurements of the expansion of the universe don’t add up

Posted by in categories: cosmology, evolution, physics

Physicists use two types of measurements to calculate the expansion rate of the universe, but their results do not coincide, which may make it necessary to update the cosmological model. “It’s like trying to thread a cosmic needle,” explains researcher Licia Verde of the University of Barcelona, co-author of an article on the implications of this problem.

More than a hundred scientists met this summer at the Kavli Institute for Theoretical Physics at the University of California (U.S.) to try to clarify what is happening with the discordant data on the expansion rate of the , an issue that affects the very origin, evolution and fate of our cosmos. Their conclusions have been published in Nature Astronomy journal.

“The problem lies in the Hubble constant (H0), a parameter which value—it is actually not a constant because it changes with time—indicates how fast the Universe is currently expanding,” points out cosmologist Licia Verde, an ICREA researcher at the Institute of Cosmos Sciences of the University of Barcelona (ICC-UB) and the main author of the article.

Nov 18, 2019

Life-long epigenetic programming of cortical architecture

Posted by in categories: biotech/medical, evolution, food, genetics, life extension, neuroscience

The evolution of human diets led to preferences toward polyunsaturated fatty acid (PUFA) content with ‘Western’ diets enriched in ω-6 PUFAs. Mounting evidence points to ω-6 PUFA excess limiting metabolic and cognitive processes that define longevity in humans. When chosen during pregnancy, ω-6 PUFA-enriched ‘Western’ diets can reprogram maternal bodily metabolism with maternal nutrient supply precipitating the body-wide imprinting of molecular and cellular adaptations at the level of long-range intercellular signaling networks in the unborn fetus. Even though unfavorable neurological outcomes are amongst the most common complications of intrauterine ω-6 PUFA excess, cellular underpinnings of life-long modifications to brain architecture remain unknown. Here, we show that nutritional ω-6 PUFA-derived endocannabinoids desensitize CB1 cannabinoid receptors, thus inducing epigenetic repression of transcriptional regulatory networks controlling neuronal differentiation. We found that cortical neurons lose their positional identity and axonal selectivity when mouse fetuses are exposed to excess ω-6 PUFAs in utero. Conversion of ω-6 PUFAs into endocannabinoids disrupted the temporal precision of signaling at neuronal CB1 cannabinoid receptors, chiefly deregulating Stat3-dependent transcriptional cascades otherwise required to execute neuronal differentiation programs. Global proteomics identified the immunoglobulin family of cell adhesion molecules (IgCAMs) as direct substrates, with DNA methylation and chromatin accessibility profiling uncovering epigenetic reprogramming at 1400 sites in neurons after prolonged cannabinoid exposure. We found anxiety and depression-like behavioral traits to manifest in adult offspring, which is consistent with genetic models of reduced IgCAM expression, to suggest causality for cortical wiring defects. Overall, our data uncover a regulatory mechanism whose disruption by maternal food choices could limit an offspring’s brain function for life.


  • Immediate Communication
  • Published: 18 November 2019
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Nov 14, 2019

How human brain development diverged from great apes

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

Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Institute of Molecular and Clinical Ophthalmology Basel, and ETH Zurich, Switzerland, have presented new insights into the development of the human brain and differences in this process compared to other great apes. The study reveals features of brain development that are unique to humans, and outlines how these processes have diverged from those in other primates.

Since humans diverged from a common ancestor shared with chimpanzees and the other great apes, the has changed dramatically. However, the genetic and developmental processes responsible for this divergence are not understood. Cerebral organoids (brain-like tissues), grown from stem cells in a dish, offer the possibility to study the evolution of early brain development in the laboratory.

Sabina Kanton, Michael James Boyle and Zhisong He, co-first authors of the study, together with Gray Camp, Barbara Treutlein and colleagues analyzed human through their development from to explore the dynamics of gene expression and regulation using methods called single-cell RNA-seq and ATAC-seq. The authors also examined chimpanzee and macaque cerebral organoids to understand how organoid development differs in humans.