Menu

Blog

Archive for the ‘evolution’ category: Page 94

Mar 26, 2021

Three-dimensional, multifunctional neural interfaces for cortical spheroids and engineered assembloids

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

Three-dimensional (3D), submillimeter-scale constructs of neural cells, known as cortical spheroids, are of rapidly growing importance in biological research because these systems reproduce complex features of the brain in vitro. Despite their great potential for studies of neurodevelopment and neurological disease modeling, 3D living objects cannot be studied easily using conventional approaches to neuromodulation, sensing, and manipulation. Here, we introduce classes of microfabricated 3D frameworks as compliant, multifunctional neural interfaces to spheroids and to assembloids. Electrical, optical, chemical, and thermal interfaces to cortical spheroids demonstrate some of the capabilities. Complex architectures and high-resolution features highlight the design versatility. Detailed studies of the spreading of coordinated bursting events across the surface of an isolated cortical spheroid and of the cascade of processes associated with formation and regrowth of bridging tissues across a pair of such spheroids represent two of the many opportunities in basic neuroscience research enabled by these platforms.

Progress in elucidating the development of the human brain increasingly relies on the use of biosystems produced by three-dimensional (3D) neural cultures, in the form of cortical spheroids, organoids, and assembloids (1–3). Precisely monitoring the physiological properties of these and other types of 3D biosystems, especially their electrophysiological behaviors, promises to enhance our understanding of the interactions associated with development of the nervous system, as well as the evolution and origins of aberrant behaviors and disease states (4–8). Conventional multielectrode array (MEA) technologies exist only in rigid, planar, and 2D formats, thereby limiting their functional interfaces to small areas of 3D cultures, typically confined to regions near the bottom contacting surfaces.

Mar 18, 2021

New Technique Reveals Genes Underlying Human Evolution

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

Summary: A new technique which involves fusing human and chimpanzee skin cells that have been modified to act like stem cells, allowed researchers to identify two novel genetic differences between humans and chimps.

Source: Stanford University.

One of the best ways to study human evolution is by comparing us with nonhuman species that, evolutionarily speaking, are closely related to us. That closeness can help scientists narrow down precisely what makes us human, but that scope is so narrow it can also be extremely hard to define. To address this complication, researchers from Stanford University have developed a new technique for comparing genetic differences.

Mar 14, 2021

How Far Should Humans Go to Help Species Adapt?

Posted by in categories: climatology, evolution, sustainability

A project to teach threatened marsupials to avoid feral cats is among a host of “assisted evolution” efforts to help animals in the face of climate change.

Mar 12, 2021

Photosynthesis tunes quantum-mechanical mixing of electronic and vibrational states to steer exciton energy transfer

Posted by in categories: biological, evolution, quantum physics

Photosynthetic light-harvesting antennae transfer energy toward reaction centers with high efficiency, but in high light or oxidative environments, the antennae divert energy to protect the photosynthetic apparatus. For a decade, quantum effects driven by vibronic coupling, where electronic and vibrational states couple, have been suggested to explain the energy transfer efficiency, but questions remain whether quantum effects are merely consequences of molecular systems. Here, we show evidence that biology tunes interpigment vibronic coupling, indicating that the quantum mechanism is operative in the efficient transfer regime and exploited by evolution for photoprotection. Specifically, the Fenna–Matthews–Olson complex uses redox-active cysteine residues to tune the resonance between its excitons and a pigment vibration to steer excess excitation toward a quenching site.

Photosynthetic species evolved to protect their light-harvesting apparatus from photoxidative damage driven by intracellular redox conditions or environmental conditions. The Fenna–Matthews–Olson (FMO) pigment–protein complex from green sulfur bacteria exhibits redox-dependent quenching behavior partially due to two internal cysteine residues. Here, we show evidence that a photosynthetic complex exploits the quantum mechanics of vibronic mixing to activate an oxidative photoprotective mechanism. We use two-dimensional electronic spectroscopy (2DES) to capture energy transfer dynamics in wild-type and cysteine-deficient FMO mutant proteins under both reducing and oxidizing conditions. Under reducing conditions, we find equal energy transfer through the exciton 4–1 and 4–2–1 pathways because the exciton 4–1 energy gap is vibronically coupled with a bacteriochlorophyll-a vibrational mode.

Mar 9, 2021

Simulations of the Universe are Getting Better and Better at Matching Reality

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

How can you possibly use simulations to reconstruct the history of the entire universe using only a small sample of galaxy observations? Through big data, that’s how.

Theoretically, we understand a lot of the physics of the history and evolution of the universe. We know that the universe used to be a lot smaller, denser, and hotter in the past. We know that its expansion is accelerating today. We know that the universe is made of very different things, including galaxies (which we can see) and dark matter (which we can’t).

We know that the largest structures in the universe have evolved slowly over time, starting as just small seeds and building up over billions of years through gravitational attraction.

Mar 5, 2021

Episode 40 — Cosmic Cataclysms And The Evolution Of Intelligent Life On Earth

Posted by in category: evolution

Great new episode with evolutionary paleobiologist Bruce Lieberman; the discussion covers the gamut from very ancient intertidal RNA pools to Trilobites to the emergence of Hominids on the East African savannas. Well worth a listen.


I welcome renowned evolutionary paleobiologist Bruce S. Lieberman, a professor at the University of Kansas in Lawrence, who is an expert on how cosmic cataclysms have impacted the evolution of life here on Earth. Massive nearby supernovae, gamma-ray bursts (GRBs) as well as asteroidal and cometary impactors have each played a role in our planet’s long tape of life. And if we were able to rewind that tape and roll the die once more? Would intelligent life have manifested itself here at all? This lively episode delves into our long road from Trilobite to Human Intelligence.

Continue reading “Episode 40 --- Cosmic Cataclysms And The Evolution Of Intelligent Life On Earth” »

Mar 2, 2021

Dr. John S Torday — Lundquist Institute / UCLA — Aging And Disease As A Process Of Reverse Evolution

Posted by in categories: biotech/medical, chemistry, evolution, genetics, information science, life extension, singularity

Dr. John Torday, Ph.D. is an Investigator at The Lundquist Institute of Biomedical Innovation, a Professor of Pediatrics and Obstetrics/Gynecology, and Faculty, Evolutionary Medicine, at the David Geffen School of Medicine at UCLA, and Director of the Perinatal Research Training Program, the Guenther Laboratory for Cell-Molecular Biology, and Faculty in the Division of Neonatology, at Harbor-UCLA Medical Center.

Dr. Torday studies the cellular-molecular development of the lung and other visceral organs, and using the well-established principles of cell-cell communication as the basis for determining the patterns of physiologic development, his laboratory was the first to determine the complete repertoire of lung alveolar morphogenesis. This highly regulated structure offered the opportunity to trace the evolution of the lung from its unicellular origins forward, developmentally and phylogenetically. The lung is an algorithm for understanding the evolution of other physiologic properties, such as in the kidney, skin, liver, gut, and central nervous system. Such basic knowledge of the how and why of physiologic evolution is useful in the effective diagnosis and treatment of disease.

Continue reading “Dr. John S Torday — Lundquist Institute / UCLA — Aging And Disease As A Process Of Reverse Evolution” »

Mar 1, 2021

“At times

Posted by in categories: evolution, space

it may seem as if the entire prior history of the Universe led us to this pivotal moment of realization that we are the ‘brain cells’ of a larger planetary superorganism, progressively morphing into one Global Mind.”-Alex Vikoulov.

*My magnum opus The Syntellect Hypothesis: Five Paradigms of the Mind’s Evolution (2020), where I share my deepest insights and far-reaching foresights, is now available as eBook, paperback, hardcover, audiobook on Amazon: https://www.amazon.com/Syntellect-Hypothesis-Paradigms-Minds…atfound-20
#SyntellectHypothesis

Mar 1, 2021

The Syntellect Hypothesis: Five Paradigms of the Mind’s Evolution: Vikoulov, Alex M., Tuynman PhD, Antonin: 9781733426145: Amazon.com: Books

Posted by in categories: evolution, space

“At times, it may seem as if the entire prior history of the Universe led us to this pivotal moment of realization that we are the ‘brain cells’ of a larger planetary superorganism, progressively morphing into one Global Mind.”-Alex Vikoulov.

*My magnum opus The Syntellect Hypothesis: Five Paradigms of the Mind’s Evolution (2020), where I share my deepest insights and far-reaching foresights, is now available as eBook, paperback, hardcover, audiobook on Amazon:

#SyntellectHypothesis

Continue reading “The Syntellect Hypothesis: Five Paradigms of the Mind’s Evolution: Vikoulov, Alex M., Tuynman PhD, Antonin: 9781733426145: Amazon.com: Books” »

Mar 1, 2021

Whales and dolphins can resist cancer and their DNA reveals why

Posted by in categories: biotech/medical, evolution

Now, Tejada-Martinez and her colleagues have studied the evolution of 1077 tumour suppressor genes (TSGs). In all, they compared the evolution of the genes in 15 mammalian species, including seven cetacean species.

Genes regulating DNA damage, tumour spread and the immune system were positively selected among the cetaceans. The team also found that cetaceans gained and lost TSGs at a rate 2.4 times higher than in other mammals.

It’s not like we’re gonna be taking whale genes and putting them into humans and making humans cancer resistant, says Lynch. But if you can find the genes that play a role in tumour suppression in other animals, and if you could figure out what they’re doing, maybe you can make a drug that mimics that for human treatment…

Page 94 of 149First9192939495969798Last