Category: 7. Science

A new research paper featured on the cover of Volume 17, Issue 7 of Aging (Aging-US) was published on July 25, 2025, titled “Systemic factors in young human serum influence in vitro responses of human skin and bone marrow-derived blood cells in a microphysiological co-culture system.”

The study, led by first author Johanna Ritter and corresponding author Elke Grönniger from Beiersdorf AG, Research and Development Hamburg, shows that components in young human blood serum can help restore youthful properties to skin, but only when bone marrow cells are also present. This discovery highlights the role of bone marrow in supporting skin health and may allow for novel approaches aimed at slowing or reversing visible signs of aging.

The research explored how factors present in blood serum, already known to influence aging in animal studies, act on human cells. Using an advanced system that mimics human circulation, the researchers connected a 3D skin model with a 3D bone marrow model. They found that young human serum alone was not enough to rejuvenate skin. However, when bone marrow cells were present, these serum factors changed the activity of those cells, which then secreted proteins that rejuvenated skin tissue.

“Interestingly, we detected a significant increase in Ki67 positive cells in the dynamic skin model co-cultured with BM model and young serum compared to the model co-cultured with BM and old serum, indicating an improved regenerative capacity of the tissue.”

Detailed analysis indicated that young serum stimulated the bone marrow to produce a group of 55 proteins, with 7 of them demonstrating the ability to boost cell renewal, collagen production, and other features associated with youthful skin. These proteins included factors that improved energy production in cells and reduced signs of cellular aging. Without the interaction between skin and bone marrow cells, these rejuvenating effects did not occur.

This finding explains why earlier experiments in mice, where young and old animals shared a blood supply, showed rejuvenation across organs. It suggests that bone marrow-derived cells are critical messengers that transform signals from blood into effects on other tissues, including the skin.

While these results are preclinical and not from human trials, they offer a starting point for new strategies in regenerative medicine and skin care. By identifying specific proteins that may carry rejuvenating signals, the study points to a new way to address age-related changes. Researchers emphasize that further studies will be needed to confirm these effects in humans and to test how these proteins can be safely and effectively applied in future therapies.

Overall, this research is an important step in understanding how young blood serum factors influence human tissue and could guide the development of novel methods to maintain healthier skin as people age.

“A deep layer of warm seawater is literally taller than a shallow layer of warm water,” said Josh Willis, Sentinel-6B project scientist at NASA’s Jet Propulsion Laboratory in Southern California. So sea surface height can be used as a proxy for the amount of heat in the ocean.

Fueling Hurricanes

There are two main ways that forecasters use sea level measurements, said Mark DeMaria, a senior research scientist at Colorado State University in Fort Collins. One way is to help set the proper ocean conditions in ocean-atmosphere hurricane forecast models utilized by the National Hurricane Center.

The second way is by feeding sea level data into machine learning models that forecasters use to predict whether a hurricane will undergo rapid intensification, where its wind speeds increase by 35 mph (56 kph) or more within 24 hours. Meteorologists include both water temperature measurements from sensors drifting in the ocean and sea surface height data collected by Sentinel-6 Michael Freilich as well as other satellites.

Hurricanes churn the ocean as they pass overhead, mixing the top layers of seawater. If the storm encounters a shallow pool of warm seawater, its winds can stir things up, pulling cooler waters from the depths to the surface. This can hinder rapid intensification. But if the warm pool of seawater extends deep into the ocean, those winds will only stir up more warm water, potentially resulting in the hurricane’s rapid intensification.

“Hurricane Milton is a perfect example of this,” said DeMaria, who was previously a branch chief at the National Hurricane Center in Miami and helped to develop hurricane intensity forecast models. Milton experienced an intense period of rapid intensification — an event that was forecast using a model fed partly with data from Sentinel-6 Michael Freilich. From Oct. 6 to Oct. 7, 2024, Milton exploded from a Category 1 hurricane to a Category 5, producing wind speeds as high as 180 mph (289 kph). The storm weakened to a Category 3 — still a major hurricane — by the time it made landfall near Sarasota, Florida, on Oct. 9.

Forecast Improvements

While the U.S.-European series of sea level satellites began collecting measurements in 1992, it wasn’t until the early 2000s that meteorologists started working with data from satellites in operational hurricane intensity forecasts such as the ones used by the National Hurricane Center. Before then, forecasts relied on models and ocean surface temperature measurements that weren’t always able to identify warm, deep pools of seawater that could induce rapid intensification in a hurricane.

Improvement efforts got a boost when the U.S. federal government started a program in 2007 aimed at advancing these types of forecasts. Since then, the program has helped move improvements made in the research realm — such as in hurricane forecast reliability and accuracy, extensions in the lead time for predictions, and reduced forecast uncertainty — into operational use.

The investment has been money well spent, said Renato Molina, an economist at the University of Miami who has analyzed the economic impact of improving hurricane forecasts. An accurate, timely forecast can give communities time to prepare, such as by boarding up homes and businesses or evacuating an area. The monetary savings can reach into the billions, he added.

While a host of atmospheric and oceanic characteristics go into hurricane forecasts, the inclusion of sea level data from satellites like Sentinel-6 Michael Freilich and, soon, Sentinel-6B has been an important addition. “We need data from sensors in the ocean as well as satellite data — they go hand-in-hand,” said DeMaria. “It would be impossible to do what we do without the satellites.”

More About Sentinel-6B

Sentinel-6/Jason-CS was jointly developed by ESA, EUMETSAT, NASA, and NOAA, with funding support from the European Commission and technical support from France’s space agency CNES (Centre National d’Études Spatiales).

NASA JPL, a division of Caltech in Pasadena, contributed three science instruments for each Sentinel-6 satellite: the Advanced Microwave Radiometer, the Global Navigation Satellite System – Radio Occultation, and the Laser Retroreflector Array. NASA is also contributing launch services, ground systems supporting operation of the NASA science instruments, the science data processors for two of these instruments, and support for the U.S. members of the international Ocean Surface Topography Science Team.

For more about Sentinel-6/Jason-CS, visit:

https://sealevel.jpl.nasa.gov/missions/jason-cs-sentinel-6

The James Webb Space Telescope’s (JWST) newest images offer a dazzling preview of the Sun’s eventual fate.

NASA’s JWST peered at the planetary nebula NGC 6072 using its near- and mid-infrared cameras, revealing incredible details that would otherwise be hidden. The new portrait of NGC 6072 looks three-dimensional, like it’s jumping off the screen.

Webb used both its NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to capture NGC 6072, and both cameras capture details that are impossible to see in visible light. In NIRCam’s case, it sees NGC 6072’s complex outflows of cooling molecular gas, including molecular hydrogen. While NIRCam can peer through cosmic dust, MIRI’s detectors, tuned for longer wavelengths, see much of this dust as an eerie blue.

NIRCam also shows that the planetary nebula is multi-polar, meaning that there are likely two stars involved.

“Specifically, a companion star is interacting with an aging star that had already begun to shed some of its outer layers of gas and dust,” NASA writes.

NGC 6072 is a planetary nebula in the southern constellation Scorpius. It is located just over 3,000 light-years away from Earth, making it a relatively very near neighbor.

Planetary nebulae like NGC 6072 were discovered back in the 1700s, and NGC 6072 specifically was discovered by British astronomer John Herschel in 1837. The term “planetary nebula” is misleading, as these often-beautiful cosmic objects, favorite targets of many amateur astronomers and astrophotographers, have nothing to do with planets whatsoever.

Instead, a planetary nebula forms when an intermediate mass star (about one to eight solar masses) reaches the end of its life. Unlike more massive stars that die in a remarkable explosion — a supernova — intermediate-mass stars don’t have enough material to support such a bombastic death.

Instead, once intermediate-mass stars run out of the fuel required for nuclear fusion, their outer shell begins growing while the inner core shrinks. As the core shrinks, its gravitational forces decrease, and the star’s outer layer breaks free, growing more and more, sometimes enveloping the planets that orbit it.

This is a vital process for the Universe’s continued evolution, as not only are the star’s initial chemicals released into the cosmos, so too are new atoms that the star formed during its life. Once the core can no longer keep everything together, chemicals and elements float into space, including metals, forever changing the composition of the dead star’s host galaxy and providing the ingredients required for new stars and planets to form.

Scientists expect that this is the precise fate that awaits the Sun. It is anticipated that the Sun will go through this process in about five billion years.

Image credits: NASA, ESA, CSA, STScI

DNA that humans acquired from ancient viruses plays a key role in switching parts of our genetic code on and off, a new study has found.

Nearly half of the human genome consists of segments called transposable elements (TEs), also known as “jumping genes” because they can hop around the genome. Some of these TEs are remnants of ancient viruses that embedded themselves in our ancestors’ genomes and have been passed down over millions of years.

Our solar system’s resident ring-bearer Saturn will be visible with its iconic rings on August 11th-12th.

It’s the first time in 15 years that the southern face of Saturn’s rings will reach a tilt of 3″. It will be visible from Earth through a basic telescope, and the perfect opportunity for introducing newbies or children to the majesty of Saturn.

That’s just one of three spectacles Saturn will stage in the night sky this month. Next week it will pass in conjunction with distant Neptune, and later in August, for those dedicated stargazers, the second-largest planet will darken under a shadow cast by its large moon Titan.

Here’s how to partake in the Saturn spectacular.

On August 3rd at 2:04 a.m. US Eastern Time, Titan’s shadow will darken Saturn’s disk, taking about 17 minutes to become visibile. By about 4:30 a.m. EDT, the shadow sits midway across the disk.

On August 6th, Neptune and Saturn undergo the second of three conjunctions this year. Both objects rise together for a period towards the beginning of the month, and can be found low in the eastern sky in the western part of the constellation Pisces.

Neptune is easily seen through a telescope hovering due north of Saturn, but will even be visible with binoculars. Viewing both planets together is rare, according to Astronomy.com, but during this conjunction they will fit within a single lens view.

Neptune is 1.9 billion miles away from Saturn, and the diameter of Saturn’s rings will be more than 5-times larger than Neptune. Fun fact: Neptune also has rings—they’re piercing blue like the planet itself.

On the night of August 11th into early morning of August 12th, Saturn’s rings will tilt 3 degrees, allowing stargazers to see the flat undersurface rather than just the band.

For those on Pacific or Mountain Time in the US, consider turning up for the second Titan shadow event on August 18th, 10:26 p.m. PDT / 11:26 p.m. Mountain. Two and a half hours later local time, the shadow will sit in the middle of the disk.

SHARE August’s Stargazing Offerings With Your Friends Who Enjoy The Stars…

Motivated by the diversity of circumstellar planets in binary stars and the strong effects of the secular resonances of Jupiter and Saturn on the formation and architecture of the inner solar system, we have launched an expansive project on studying the effects of secular resonances on the formation of terrestrial planets around a star of a moderately close binary.

As the first phase of our project, we present here the general theory of secular resonances in dual-star systems where the primary hosts two giant planets. Using the concept of generalized disturbing function, we derive the formula for the locations of secular resonances and show that in systems where the perturbation of the secondary star is stronger, the locations of secular resonances are farther way from the primary and closer to the giant planets.

The latter implies that in such systems, terrestrial planet formation has a larger area to proceed with more of the protoplanetary disk being available to it. To demonstrate the validity of our theoretical results, we simulated the evolution of a protoplanetary disk interior to the inner giant planet.

Results, in addition to confirming our theoretical predictions, pointed to an important finding: In binary stars, the perturbation of the secondary suppresses the secular resonances of giant planets. Simulations also show that as the disk loses material, secular resonances move inward, scattering objects out of the disk and/or facilitating their collisional growth. We present results of our study and discuss their implications for the simulations of terrestrial planet formation.

Nader Haghighipour, Michael Andrew

Comments: 26 pages, 9 figures, 4 tables. Accepted for publication in ApJ. This is the first of a two-article series on secular resonances and their effects on planet formation in circumstellar planetary systems in moderately closed binary stars
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2507.17092 [astro-ph.EP] (or arXiv:2507.17092v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2507.17092
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Journal reference: The Astronomical Journal, 170:117, August 1, 2025
Related DOI:
https://doi.org/10.3847/1538-3881/ad82e8
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Submission history
From: Nader Haghighipour
[v1] Wed, 23 Jul 2025 00:18:20 UTC (2,541 KB)
https://arxiv.org/abs/2507.17092

Astrobiology,

August 1, 2025 by Marni Ellery

UC Berkeley professor Junqiao Wu has spent over a decade working with vanadium dioxide, a compound known for its ability to shift between insulating and metallic states. By harnessing this unusual property, he and his lab have developed innovative technologies ranging from “smart” roofing materials to ultra-precise thermography techniques.

Now, they have discovered a new application for this versatile material. In a study published today (August 1) in Nature Materials, Wu and his team demonstrated how vanadium dioxide can also be used to help electronic sensors more efficiently interface with wet, salty systems — a persistent problem for scientists and engineers.

Using this material, the researchers created a new in-memory sensor, or memsensor, that can both detect and remember its chemical environment, enabling it to adapt to challenging aqueous conditions. And, unlike conventional designs, it can do all of this without external power input or complex circuitry.

“This breakthrough could pave the way for simpler, more energy-efficient sensors and adaptive robots capable of operating in complex environments,” said Wu, the study’s principal investigator and the Chancellor’s Professor in the Department of Materials Science and Engineering. “It may also open exciting possibilities for next-generation computing systems that integrate memory and sensing in liquid settings, much like how biological neurons function in the brain’s wet, ionic environment.”

Based on what they knew about vanadium dioxide, the researchers wondered if the material could potentially be used to help electronic sensors efficiently operate under such conditions.

“While it was already known that vanadium dioxide can switch phases and ‘remember’ changes when doped with certain ions, we wanted to explore whether this could automatically happen in water with mobile ions, similar to how nerve cells in living organisms sense and store information with ion motion,” said Ruihan Guo, lead author of the study and a graduate student researcher in Wu’s lab.

To create their memsensor, the researchers attached a thin layer of vanadium dioxide to a small piece of indium, an extremely soft, silvery metal. When the device is placed in salt water, indium releases ions where the solution touches the vanadium dioxide. With the built-in electric fields at the solid-liquid interface, the ions are drawn to vanadium dioxide’s surface, causing part of the material to turn metallic — a resistance change that persists over time.

This shift in conductivity effectively “records” the history of salt exposure, and the rate of conductivity change correlates with the salt concentration. More importantly, the memsensor can sense and store this information without the need for any external voltage.

“Using vanadium dioxide’s ability to switch between insulating and metallic states, we were able to create a fast, energy-efficient, in-memory sensor capable of operating in salt solutions and retaining information about the salt concentration even when the sensor is taken out of the solutions,” said Guo.

While engineering their memsensor, the researchers took inspiration from the tiny nematode C. elegans. “This worm uses specialized neurons to remember salt exposure and guide its movement toward or away from certain environments when searching for food,” said Guo. “Mimicking this behavior, we used our sensor to direct a small robotic boat to navigate salt gradients — avoiding undesirable zones and seeking favorable ones — based on its prior salt exposure history.”

Wu explained that their memsensing technology may someday be useful in designing low-power aquatic robotics. Such robots could explore underwater or contaminated environments while adapting their movements like living organisms.

“In a broader sense, the underlying principles point toward the possibility of brain-inspired computing in wet environments — just like our own brain, which operates in a salty, aqueous medium,” he said. “In such systems, devices could sense, store and process chemical information spontaneously, all within a single, integrated platform.”

This work was supported by the U.S. Department of Energy Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division. For additional details and a complete list of authors, view the study.

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The transformer: A material’s unusual behavior brings potential advances to industry and science

Caltech scientists have developed a method to create metallic objects of a precisely specified shape and composition, giving them unprecedented control of the metallic mixtures, or alloys, they create and the enhanced properties those creations will display. Want a stent that is biocompatible and mechanically robust? How about strong but lightweight satellite components that can operate in space for decades? The new technique can tell scientists exactly which combination of metals will yield the best product. In addition, it offers a route to making alloys with beneficial properties determined by their underlying structure, such as surprisingly strong copper–nickel alloys.

“If you look at how metallurgy has been done for centuries, in broad strokes, you nearly always start with a raw ore, which is then thermally and/or chemically treated and refined, to produce the desired metal or alloy. And basically, the mechanical properties of the metals produced this way are limited,” says Julia R. Greer, the Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering at Caltech and executive officer for applied physics and materials science at Caltech. “What we are showing is that you can actually fine-tune the chemical composition and the microstructure of metallic materials, substantially enhancing their mechanical resilience.”

Greer and her colleagues describe the new method in a paper published online by the journal Small. The lead author of the paper is Thomas T. Tran (PhD ’25), and the second author is Rebecca Gallivan (PhD ’23), a former member of the Greer lab who is now an assistant professor of engineering at Dartmouth College.

The new technique builds on previous work from the Greer lab in which the scientists showed how to use a form of 3D printing, or additive manufacturing, to make complex microscale metal structures. Previously, the technique, called hydrogel-infusion additive manufacturing (HIAM), had been used to carefully build structures from a single type of metal. In the new work, Tran has figured out a way to infuse more than one metal at a time, creating copper–nickel alloys containing custom percentages of copper and nickel—differences that matter when it comes to material properties.

The process begins with 3D printing of an organic hydrogel material, depositing the polymer resin precisely where it is wanted, layer by layer, to create a gel-like scaffold. That scaffold is then infused with metal ions by pouring a liquid solution of metallic salts over the structure. Next, in a process called calcination, the scientists burn the material, removing all the organic content and leaving behind the metals. Since this is done in the presence of oxygen, what is left is a mixture of metal oxides.

In an innovative next step, called reductive annealing, Tran raises the temperature in a hydrogen environment causing most of the oxygen to diffuse back out of the solid; it then reacts with hydrogen to form water vapor. This leaves behind a metallic structure of the desired shape that is an alloy of the two added metals.

“The composition can be varied in whatever manner you like, which has not been possible in traditional metallurgy processes,” Greer explains. “One of our colleagues described this work as bringing metallurgy into the 21st century.”

By analyzing the microstructure, which includes the orientation of the individual crystal grains and the boundaries among them within the alloys they produced, and by mechanically testing the materials, the scientists were able to reveal more about the special alloys made with the new technique.

“This lays the groundwork for thinking about 3D-printed alloy design in a unique way from other microscale additive manufacturing techniques,” says Gallivan. “We see that the processing environment leads to very different microstructures in comparison to other methods.”

Using a transmission electron microscope (TEM) at the UC Irvine Materials Research Institute, the Caltech researchers were able to show that alloys produced using their HIAM method form more homogenously, resulting in higher degrees of symmetry throughout their crystal structure, Tran explains. The shape, size, and orientation of metal grains are influenced by the transition between oxide and metal during reductive annealing. At elevated temperatures, pores form as water vapor escapes. Metal grain growth is slowed by these pores and oxides. The new work shows that this growth is modified by the types of oxides present in these 3D-printed metals.

As a result, the new paper shows that the strength of alloys created by HIAM is determined not only by the size of the grains within the metals—as was previously thought— but also by their composition. A Cu12Ni88 alloy with 12 atoms of copper for every 88 atoms of nickel, for example, is nearly four times as strong as a Cu59Ni41 alloy that has copper and nickel in a 59/41 ratio.

The TEM studies also revealed that the HIAM process leaves these alloys with tiny oxide inclusions that contribute to the materials’ exceptional strength. “Because of the complex ways in which metal is formed during this process, we find nanoscale structures rich with metal–oxide interfaces that contribute to the hardening of our alloys by up to a factor of four,” Tran says.

The paper is titled “Multiscale Microstructural and Mechanical Characterization of Cu–Ni Binary Alloys Reduced During Hydrogel Infusion-Based Additive Manufacturing (HIAM).” The work was supported by the US Department of Energy’s Basic Energy Sciences program and by a National Science Foundation graduate fellowship.