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Circadian Timekeeping Through Nutritional and Metabolic Sensory Networks

Circadian rhythms are predictable biological patterns that recur about every 24 h and, in mammals such as humans, are entrained to daylight by the hypothalamic suprachiasmatic nucleus (SCN). Although light is a potent zeitgeber for the SCN, cells outside of the SCN can synchronize to daily nutrient and metabolic cues. In these tissues, nutrient metabolic processes are regulated by the molecular clock in anticipation of food availability or scarcity. Furthermore, nutrients and metabolic processes themselves may act upon members of the molecular clock to regulate their expression and activity. These interactions maintain synchrony between the SCN and food-entrainable clocks when activity and nutrient intake align.

A generative AI framework unifies human multi-omics to model aging, metabolic health, and intervention response

Circadian rhythms are predictable biological patterns that recur about every 24 h and, in mammals such as humans, are entrained to daylight by the hypothalamic suprachiasmatic nucleus (SCN). Although light is a potent zeitgeber for the SCN, cells outside of the SCN can synchronize to daily nutrient and metabolic cues. In these tissues, nutrient metabolic processes are regulated by the molecular clock in anticipation of food availability or scarcity. Furthermore, nutrients and metabolic processes themselves may act upon members of the molecular clock to regulate their expression and activity. These interactions maintain synchrony between the SCN and food-entrainable clocks when activity and nutrient intake align. However, the light-entrainable SCN and food-entrainable clocks can become desynchronized, particularly in modern society where humans are commonly exposed to shift work and jet lag. Therefore, the mechanisms for sensing nutrients at specific times of day are critical components of circadian timekeeping and organismal homeostasis. In the following narrative review, we aim to synthesize current evidence on time-of-day-dependent nutrient sensing in mammalian systems, examine how nutrient-derived signals and metabolic processes interact with molecular clock mechanisms across cellular and tissue levels, and evaluate the integration of central and peripheral clocks in regulating gene expression, energy utilization, and organismal homeostasis, including the impacts of feeding cycles and circadian disruption. While previous reviews have discussed circadian nutrient metabolism, this review provides conceptual support for the role of nutrients as time-of-day signaling mechanisms.

Cell membranes may store memories after electrical stimulation

The science of memories has been pursued and studied since the days of ancient Greece and Aristotle. Today, research conducted by Dima Bolmatov, assistant professor in the Department of Physics & Astronomy at Texas Tech University, is considering how memories are stored on a cellular level.

Bolmatov’s research centers on lipid bilayers, membranes that serve as a continuous barrier around cells. These membranes, he noted, were traditionally viewed as passive barriers.

“I began to see that they behave more like dynamic, adaptive materials,” he stated. “They respond to electrical stimulation, retain history and exhibit collective behavior. This realization suggests that membranes themselves may participate in information processing, bridging physics and biology in a fundamentally new way.”

The physics of brain development: How cells pull together to form the neural tube

In about one out of every 1,000 pregnancies, the neural tube, a key nervous system structure, fails to close properly. Georgia Tech physicists are now helping explain why this happens, having uncovered the physics that drive neural tube closure in a pregnancy’s earliest stages.

Working with collaborators at University College London (UCL), Georgia Tech researchers used computer models to reveal how, during early development, forces generated by cells physically pull the neural tube closed—like a drawstring. This discovery offers new insight into a critical process that—when disrupted—can result in severe birth defects such as spina bifida.

“Understanding a complex developmental process like neural tube closure requires a highly interdisciplinary approach,” said Shiladitya Banerjee, an associate professor in the School of Physics. “By combining advanced biological imaging with theoretical physics, we were able to uncover the mechanical rules that drive cells to close the tube. My lab builds computational models to uncover the physical rules of living systems. The neural tube is an ideal focus because its formation requires incredible mechanical coordination.”

Songbird connectome reveals tunneling of migratory neurons in the adult striatum

Despite its small size—typically only several inches, beak to tail—the zebra finch is a remarkable learner. A songbird native to Australia, it’s renowned for its ability to pick up new songs.

That talent has made it a favorite of scientists studying how animal brains imprint new skills, particularly vocal learning, or the capacity to perfect new sounds. And now researchers at Boston University have discovered another quirk to the zebra finch brain—one that could also have implications for understanding our own gray matter.

In a study that looked at the bird’s brain in unprecedented detail, they uncovered new insights into a mechanism known as neurogenesis—the birth, migration, and maturation of neurons—that may help the brain learn, add new skills, and restore and repair itself.

Observing the finch brain using a high-powered microscope, the researchers watched as new neurons bullied their way through the brain en route to bolstering existing circuits and connections. They’d expected the neurons to gingerly step around established brain structures, including more mature brain cells, to better preserve them; instead, they saw the neurons tunnel right through, squishing and shoving as they went. That may help the birds learn new things or repair damage, but it could also come with a cost to existing cells and memories.

According to the BU-led team, their findings could help explain why neurogenesis may not occur in humans beyond the womb, increasing our vulnerability to a range of brain disorders. The findings were published in Current Biology.

Abstract: Current Biology

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Ray Kurzweil: “The Biological Singularity Is Almost Here”

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Are we transcending human biology, or are we engineering our own obsolescence? The Biological Singularity is no longer science fiction. AI systems like AlphaFold 3 and ESM3 are actively rewriting the human source code, turning biology into a programmable engineering discipline. But as we approach the death of aging and the dawn of designer reality, a terrifying question emerges: what happens to the global population when the elite become mathematically and biologically superior? We explore Yuval Noah Harari’s warning of the \.

Fields as Formal Causes, with David Bentley Hart

In this conversation, Rupert Sheldrake and David Bentley Hart delve into the concept of fields in physics, discussing their nature as non-material formative causes and their historical context in scientific thought. They explore the idea that fields, such as gravitational and electromagnetic, act as top-down causes, aligning with Aristotle’s formal and final causes, and argue for a re-evaluation of these ancient concepts in modern science.

Chapter List:

00:00 — Introduction.
01:14 — Exploring Fields as Causes in Nature.
02:08 — Magnetic Fields and Formative Processes.
04:19 — Gravitational Fields and Formative Effects.
06:10 — Aristotle’s Formal and Final Causes.
07:32 — Challenges in Understanding Fields.
09:09 — Fields as Top-Down Causes.
10:34 — Morphic Fields and Formative Causation.
12:23 — Information Theory vs. Form.
14:15 — Fields and Order in Physics.
17:15 — Semantic and Syntactic Information.
18:18 — Universal Gravitational Field.
19:44 — Strong and Weak Nuclear Fields.
21:18 — History of Field Theory and Ether.
23:14 — Gilbert’s Magnetic Theory.
24:46 — Mind-like Structure in Nature.
25:39 — Combination of Top-Down and Bottom-Up Theories.
27:07 — Mechanistic Models and Their Limitations.
28:52 — Recovering Aristotelian Causality.
31:39 — Conclusion and Reflection on Fields as Modern Souls.


Dr Rupert Sheldrake, PhD, is a biologist and author best known for his hypothesis of morphic resonance. At Cambridge University, as a Fellow of Clare College, he was Director of Studies in biochemistry and cell biology. As the Rosenheim Research Fellow of the Royal Society, he carried out research on the development of plants and the ageing of cells, and together with Philip Rubery discovered the mechanism of polar auxin transport. In India, he was Principal Plant Physiologist at the International Crops Research Institute for the Semi-Arid Tropics, where he helped develop new cropping systems now widely used by farmers. He is the author of more than 100 papers in peer-reviewed journals and his research contributions have been widely recognized by the academic community, earning him a notable h-index for numerous citations. On ResearchGate his Research Interest Score puts him among the top 4% of scientists.

https://www.sheldrake.org

Physicists can’t find “now” anywhere in the universe | Jim Al-Khalili

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We would hope that the moment that we eternally live in, the “now,” would have a concrete scientific explanation. But the truth is far more complicated, says the relativity of simultaneity.

Jim Al-Khalili explains how the past and future are more fluid than we may think.

Preorder Jim Al-Khalili’s forthcoming book, On Time: The Physics That Makes the Universe, here: https://www.amazon.com/Time-Physics-T?tag=lifeboatfound-20

About Jim Al-Khalili: Jim is a multiple award-winning science communicator renowned for his public engagement around the world through writing and broadcasting and a leading academic making fundamental contributions to theoretical physics, particularly in nuclear reaction theory, quantum effects in biology, open quantum systems and the foundations of quantum mechanics. Jim is a theoretical physicist at the University of Surrey where he holds a Distinguished Chair in physics as well as a university chair in the public engagement in science. He received his PhD in nuclear reaction theory in 1989 and has published widely in the field. His current interest is in open quantum systems and the application of quantum mechanics in biology.

About Jim Al-Khalili:

Fluorescent technique reveals hidden scale of microfiber pollution from our clothes

Pollution released from our textiles is smaller and more irregular in shape than previously thought, according to new research led by The University of Manchester. In a study published in Scientific Reports, Manchester researchers—in collaboration with researchers from the University of East Anglia and Manchester Metropolitan University—have developed a new fluorescence-based method that dramatically improves the detection of microfibers released from textiles during washing and wear.

The findings suggest that conventional testing methods may have been missing a large proportion of the smallest fiber fragments, the particles most likely to persist in the environment and enter living organisms.

Every time clothes are worn or washed, microscopic fibers shed from fabrics and enter water, air and soil. Until now, accurately measuring the smallest of these fibers has been extremely difficult, limiting our understanding of their true environmental impact.

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