Tag Archives: University of Colorado

Nature’s missing evolutionary law added in new paper by leading scientists and philosophers

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An October 22, 2023 commentary by Rae Hodge for Salon.com introduces the new work with a beautiful lede/lead and more,

A recently published scientific article proposes a sweeping new law of nature, approaching the matter with dry, clinical efficiency that still reads like poetry.

“A pervasive wonder of the natural world is the evolution of varied systems, including stars, minerals, atmospheres, and life,” the scientists write in the Proceedings of the National Academy of Sciences. “Evolving systems are asymmetrical with respect to time; they display temporal increases in diversity, distribution, and/or patterned behavior,” they continue, mounting their case from the shoulders of Charles Darwin, extending it toward all things living and not.

To join the known physics laws of thermodynamics, electromagnetism and Newton’s laws of motion and gravity, the nine scientists and philosophers behind the paper propose their “law of increasing functional information.”

In short, a complex and evolving system — whether that’s a flock of gold finches or a nebula or the English language — will produce ever more diverse and intricately detailed states and configurations of itself.

And here, any writer should find their breath caught in their throat. Any writer would have to pause and marvel.

It’s a rare thing to hear the voice of science singing toward its twin in the humanities. The scientists seem to be searching in their paper for the right words to describe the way the nested trills of a flautist rise through a vaulted cathedral to coalesce into notes themselves not played by human breath. And how, in the very same way, the oil-slick sheen of a June Bug wing may reveal its unseen spectra only against the brief-blooming dogwood in just the right season of sun.

Both intricate configurations of art and matter arise and fade according to their shared characteristic, long-known by students of the humanities: each have been graced with enough time to attend to the necessary affairs of their most enduring pleasures.

…

If you have the time, do read this October 22, 2023 commentary as Hodge waxes eloquent.

An October 16, 2023 news item on phys.org announces the work in a more prosaic fashion,

A paper published in the Proceedings of the National Academy of Sciences describes “a missing law of nature,” recognizing for the first time an important norm within the natural world’s workings.

In essence, the new law states that complex natural systems evolve to states of greater patterning, diversity, and complexity. In other words, evolution is not limited to life on Earth, it also occurs in other massively complex systems, from planets and stars to atoms, minerals, and more.

It was authored by a nine-member team— scientists from the Carnegie Institution for Science, the California Institute of Technology (Caltech) and Cornell University, and philosophers from the University of Colorado.

…

An October 16, 2023 Carnegie Science Earth and Planets Laboratory news release on EurekAlert (there is also a somewhat shorter October 16, 2023 version on the Carnegie Science [Carnegie Institution of Science] website), which originated the news item, provides a lot more detail,

“Macroscopic” laws of nature describe and explain phenomena experienced daily in the natural world. Natural laws related to forces and motion, gravity, electromagnetism, and energy, for example, were described more than 150 years ago. 

The new work presents a modern addition — a macroscopic law recognizing evolution as a common feature of the natural world’s complex systems, which are characterised as follows:

  • They are formed from many different components, such as atoms, molecules, or cells, that can be arranged and rearranged repeatedly
  • Are subject to natural processes that cause countless different arrangements to be formed
  • Only a small fraction of all these configurations survive in a process called “selection for function.”   

Regardless of whether the system is living or nonliving, when a novel configuration works well and function improves, evolution occurs. 

The authors’ “Law of Increasing Functional Information” states that the system will evolve “if many different configurations of the system undergo selection for one or more functions.”

“An important component of this proposed natural law is the idea of ‘selection for function,’” says Carnegie astrobiologist Dr. Michael L. Wong, first author of the study.

In the case of biology, Darwin equated function primarily with survival—the ability to live long enough to produce fertile offspring. 

The new study expands that perspective, noting that at least three kinds of function occur in nature. 

The most basic function is stability – stable arrangements of atoms or molecules are selected to continue. Also chosen to persist are dynamic systems with ongoing supplies of energy. 

The third and most interesting function is “novelty”—the tendency of evolving systems to explore new configurations that sometimes lead to startling new behaviors or characteristics. 

Life’s evolutionary history is rich with novelties—photosynthesis evolved when single cells learned to harness light energy, multicellular life evolved when cells learned to cooperate, and species evolved thanks to advantageous new behaviors such as swimming, walking, flying, and thinking. 

The same sort of evolution happens in the mineral kingdom. The earliest minerals represent particularly stable arrangements of atoms. Those primordial minerals provided foundations for the next generations of minerals, which participated in life’s origins. The evolution of life and minerals are intertwined, as life uses minerals for shells, teeth, and bones.

Indeed, Earth’s minerals, which began with about 20 at the dawn of our Solar System, now number almost 6,000 known today thanks to ever more complex physical, chemical, and ultimately biological processes over 4.5 billion years. 

In the case of stars, the paper notes that just two major elements – hydrogen and helium – formed the first stars shortly after the big bang. Those earliest stars used hydrogen and helium to make about 20 heavier chemical elements. And the next generation of stars built on that diversity to produce almost 100 more elements.

“Charles Darwin eloquently articulated the way plants and animals evolve by natural selection, with many variations and traits of individuals and many different configurations,” says co-author Robert M. Hazen of Carnegie Science, a leader of the research.

“We contend that Darwinian theory is just a very special, very important case within a far larger natural phenomenon. The notion that selection for function drives evolution applies equally to stars, atoms, minerals, and many other conceptually equivalent situations where many configurations are subjected to selective pressure.”

The co-authors themselves represent a unique multi-disciplinary configuration: three philosophers of science, two astrobiologists, a data scientist, a mineralogist, and a theoretical physicist.

Says Dr. Wong: “In this new paper, we consider evolution in the broadest sense—change over time—which subsumes Darwinian evolution based upon the particulars of ‘descent with modification.’”  

“The universe generates novel combinations of atoms, molecules, cells, etc. Those combinations that are stable and can go on to engender even more novelty will continue to evolve. This is what makes life the most striking example of evolution, but evolution is everywhere.”

Among many implications, the paper offers: 

  1. Understanding into how differing systems possess varying degrees to which they can continue to evolve. “Potential complexity” or “future complexity” have been proposed as metrics of how much more complex an evolving system might become
  2. Insights into how the rate of evolution of some systems can be influenced artificially. The notion of functional information suggests that the rate of evolution in a system might be increased in at least three ways: (1) by increasing the number and/or diversity of interacting agents, (2) by increasing the number of different configurations of the system; and/or 3) by enhancing the selective pressure on the system (for example, in chemical systems by more frequent cycles of heating/cooling or wetting/drying).
  3. A deeper understanding of generative forces behind the creation and existence of complex phenomena in the universe, and the role of information in describing them
  4. An understanding of life in the context of other complex evolving systems. Life shares certain conceptual equivalencies with other complex evolving systems, but the authors point to a future research direction, asking if there is something distinct about how life processes information on functionality (see also https://royalsocietypublishing.org/doi/10.1098/rsif.2022.0810).
  5. Aiding the search for life elsewhere: if there is a demarcation between life and non-life that has to do with selection for function, can we identify the “rules of life” that allow us to discriminate that biotic dividing line in astrobiological investigations? (See also https://conta.cc/3LwLRYS, “Did Life Exist on Mars? Other Planets? With AI’s Help, We May Know Soon”)
  6. At a time when evolving AI systems are an increasing concern, a predictive law of information that characterizes how both natural and symbolic systems evolve is especially welcome

Laws of nature – motion, gravity, electromagnetism, thermodynamics – etc. codify the general behavior of various macroscopic natural systems across space and time. 

The “law of increasing functional information” published today complements the 2nd law of thermodynamics, which states that the entropy (disorder) of an isolated system increases over time (and heat always flows from hotter to colder objects).

* * * * *

Comments

“This is a superb, bold, broad, and transformational article.  …  The authors are approaching the fundamental issue of the increase in complexity of the evolving universe. The purpose is a search for a ‘missing law’ that is consistent with the known laws.

“At this stage of the development of these ideas, rather like the early concepts in the mid-19th century of coming to understand ‘energy’ and ‘entropy,’ open broad discussion is now essential.”

Stuart Kauffman
Institute for Systems Biology, Seattle WA

“The study of Wong et al. is like a breeze of fresh air blowing over the difficult terrain at the trijunction of astrobiology, systems science and evolutionary theory. It follows in the steps of giants such as Erwin Schrödinger, Ilya Prigogine, Freeman Dyson and James Lovelock. In particular, it was Schrödinger who formulated the perennial puzzle: how can complexity increase — and drastically so! — in living systems, while they remain bound by the Second Law of thermodynamics? In the pile of attempts to resolve this conundrum in the course of the last 80 years, Wong et al. offer perhaps the best shot so far.”

“Their central idea, the formulation of the law of increasing functional information, is simple but subtle: a system will manifest an increase in functional information if its various configurations generated in time are selected for one or more functions. This, the authors claim, is the controversial ‘missing law’ of complexity, and they provide a bunch of excellent examples. From my admittedly quite subjective point of view, the most interesting ones pertain to life in radically different habitats like Titan or to evolutionary trajectories characterized by multiple exaptations of traits resulting in a dramatic increase in complexity. Does the correct answer to Schrödinger’s question lie in this direction? Only time will tell, but both my head and my gut are curiously positive on that one. Finally, another great merit of this study is worth pointing out: in this day and age of rabid Counter-Enlightenment on the loose, as well as relentless attacks on the freedom of thought and speech, we certainly need more unabashedly multidisciplinary and multicultural projects like this one.”

Milan Cirkovic 
Astronomical Observatory of Belgrade, Serbia; The Future of Humanity Institute, Oxford University [University of Oxford]

The natural laws we recognize today cannot yet account for one astounding characteristic of our universe—the propensity of natural systems to “evolve.” As the authors of this study attest, the tendency to increase in complexity and function through time is not specific to biology, but is a fundamental property observed throughout the universe. Wong and colleagues have distilled a set of principles which provide a foundation for cross-disciplinary discourse on evolving systems. In so doing, their work will facilitate the study of self-organization and emergent complexity in the natural world.

Corday Selden
Department of Marine and Coastal Sciences, Rutgers University

The paper “On the roles of function and selection in evolving systems” provides an innovative, compelling, and sound theoretical framework for the evolution of complex systems, encompassing both living and non-living systems. Pivotal in this new law is functional information, which quantitatively captures the possibilities a system has to perform a function. As some functions are indeed crucial for the survival of a living organism, this theory addresses the core of evolution and is open to quantitative assessment. I believe this contribution has also the merit of speaking to different scientific communities that might find a common ground for open and fruitful discussions on complexity and evolution.

Andrea Roli
Assistant Professor, Università di Bologna.

Here’s a link to and a citation for the paper,

On the roles of function and selection in evolving systems by Michael L. Wong, Carol E. Cleland, Daniel Arends Jr., Stuart Bartlett, H. James Cleaves, Heather Demarest, Anirudh Prabhu, Jonathan I. Lunine, and Robert M. Hazen. Proceedings of the National Academy of Sciences (PNAS) 120 (43) e2310223120 DOI: https://doi.org/10.1073/pnas.2310223120 Published: October 16, 2023

This paper is open access.

So thin and soft you don’t notice it: new wearable tech

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An August 2, 2019 news item on ScienceDaily features some new work on wearable technology that was a bit of a surprise to me,

Wearable human-machine interfaces — devices that can collect and store important health information about the wearer, among other uses — have benefited from advances in electronics, materials and mechanical designs. But current models still can be bulky and uncomfortable, and they can’t always handle multiple functions at one time.

Researchers reported Friday, Aug. 2 [2019], the discovery of a multifunctional ultra-thin wearable electronic device that is imperceptible to the wearer.

…

I expected this wearable technology to be a piece of clothing that somehow captured health data but it’s not,

While a health care application is mentioned early in the August 2, 2019 University of Houston news release (also on EurekAlert) by Jeannie Kever the primary interest seems to be robots and robotic skin (Note: This news release originated the news item on ScienceDaily),

The device allows the wearer to move naturally and is less noticeable than wearing a Band-Aid, said Cunjiang Yu, Bill D. Cook Associate Professor of Mechanical Engineering at the University of Houston and lead author for the paper, published as the cover story in Science Advances.

“Everything is very thin, just a few microns thick,” said Yu, who also is a principal investigator at the Texas Center for Superconductivity at UH. “You will not be able to feel it.”
It has the potential to work as a prosthetic skin for a robotic hand or other robotic devices, with a robust human-machine interface that allows it to automatically collect information and relay it back to the wearer.

That has applications for health care – “What if when you shook hands with a robotic hand, it was able to instantly deduce physical condition?” Yu asked – as well as for situations such as chemical spills, which are risky for humans but require human decision-making based on physical inspection.

While current devices are gaining in popularity, the researchers said they can be bulky to wear, offer slow response times and suffer a drop in performance over time. More flexible versions are unable to provide multiple functions at once – sensing, switching, stimulation and data storage, for example – and are generally expensive and complicated to manufacture.

The device described in the paper, a metal oxide semiconductor on a polymer base, offers manufacturing advantages and can be processed at temperatures lower than 300 C.

“We report an ultrathin, mechanically imperceptible, and stretchable (human-machine interface) HMI device, which is worn on human skin to capture multiple physical data and also on a robot to offer intelligent feedback, forming a closed-loop HMI,” the researchers wrote. “The multifunctional soft stretchy HMI device is based on a one-step formed, sol-gel-on-polymer-processed indium zinc oxide semiconductor nanomembrane electronics.”

In addition to Yu, the paper’s co-authors include first author Kyoseung Sim, Zhoulyu Rao, Faheem Ershad, Jianming Lei, Anish Thukral and Jie Chen, all of UH; Zhanan Zou and Jianliang Xiao, both of the University of Colorado; and Qing-An Huang of Southeast University in Nanjing, China.

Here’s a link to and a citation for the paper,

Metal oxide semiconductor nanomembrane–based soft unnoticeable multifunctional electronics for wearable human-machine interfaces by Kyoseung Sim, Zhoulyu Rao, Zhanan Zou, Faheem Ershad, Jianming Lei, Anish Thukral, Jie Chen, Qing-An Huang, Jianliang Xiao and Cunjiang Yu. Science Advances 02 Aug 2019: Vol. 5, no. 8, eaav9653 DOI: 10.1126/sciadv.aav9653

This paper appears to be open access.

Analyzing a buckyball’s (buckminsterfullerene) quantum structure

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The work was done jointly by the US National Institute of Standards and Technology (NIST) and JILA (Joint Institute for Laboratory Astrophysics), which is operated ‘jointly’ by NIST and the University of Colorado. On to buckyballs, a nickname for buckminsterfullerenes or C60.

From a January 28, 2019 news item on ScienceDaily,

JILA researchers have measured hundreds of individual quantum energy levels in the buckyball, a spherical cage of 60 carbon atoms. It’s the largest molecule that has ever been analyzed at this level of experimental detail in the history of quantum mechanics. Fully understanding and controlling this molecule’s quantum details could lead to new scientific fields and applications, such as an entire quantum computer contained in a single buckyball.

Caption: JILA researchers used frequency combs, or “rulers of light,” to observe individual quantum energy transitions in buckyballs. Credit: Steven Burrows/JILA

There are two types of spherical objects in the image: the smooth blue ones, which are not buckyballs, and the ones with ridged spheres, which are.

A January 28, 2019 NIST news release (also on EurekAlert), which originated the news item, describes the buckyball molecule and the research in more detail,

The buckyball, formally known as buckminsterfullerene, is extremely complex. Due to its enormous 60-atom size, the overall molecule has a staggeringly high number of ways to vibrate–at least 100,000,000,000,000,000,000,000,000 vibrational quantum states when the molecule is warm. That’s in addition to the many different energy states for the buckyball’s rotation and other properties.

As described in the January 4 [2019] issue of Science, the JILA team used an updated version of their frequency comb spectroscopy and cryogenic buffer gas cooling system to observe isolated, individual energy transitions among rotational and vibrational states in cold, gaseous buckyballs. This is the first time anyone has been able to prepare buckyballs in this form to analyze its rotations and vibrations at the quantum level.

JILA is jointly operated by the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder.

Buckyballs, first discovered in 1984, have created great scientific excitement. But high-resolution spectroscopy, which can reveal the details of the molecule’s rotational and vibrational properties, didn’t work at ordinary room temperatures because the signals were too congested, NIST/JILA Fellow Jun Ye said. Low temperatures (about -138 degrees Celsius, which is -216 degrees Fahrenheit) enabled researchers to concentrate the molecules into a single rotational-vibrational quantum state at the lowest energy level and probe them with high-resolution spectroscopy.

The buckyball is the most symmetric molecule known, with a soccer-ball-like shape known as a modified icosahedron. It is small enough to be fully understood with basic quantum mechanics principles. Yet it is large enough to reveal insights into the extreme quantum complexity that emerges in huge systems.

As an example of practical applications, buckyballs could act as a pristine network of 60 atoms. The core of each atom possesses an identical property known as “nuclear spin,” which enables it to interact magnetically with its environment. Therefore, each spin could act as a magnetically controlled quantum bit or “qubit” in a quantum computer.

“If we had a buckyball made of pure isotopic carbon-13, each atom would have a nuclear spin of 1/2, and each buckyball could serve as a 60-qubit quantum computer,” Ye said. “Of course, we don’t have such capabilities yet; we would need to first capture these buckyballs in traps.”

A key part of the new quantum revolution, a quantum computer using qubits made of atoms or other materials could potentially solve important problems that are intractable using today’s machines. NIST has a major stake in quantum science

“There are also a lot of astrophysics connections,” Ye continued. “There are abundant buckyball signals coming from remote carbon stars,” so the new data will enable scientists to better understand the universe.

After they measured the quantum energy levels, the JILA researchers collected statistics on buckyballs’ nuclear spin values. They confirmed that all 60 atoms were indistinguishable, or virtually identical. Precise measurements of the buckyball’s transition energies between individual quantum states revealed its atoms interacted strongly with one another, providing insights into the complexities of its molecular structure and the forces between atoms.

For the experiments, an oven converted a solid sample of material into gaseous buckyballs. These hot molecules flowed into a cell (container) anchored to a cryogenic cold apparatus, such that the molecules were cooled by collisions with cold argon gas atoms. Then laser light at precise frequencies was aimed at the cold gas molecules, and researchers measured how much light was absorbed. The observed structure in the infrared spectrum encoded details of the quantum-mechanical energy-level structure.

The laser light was produced by an optical frequency comb, or “ruler of light,” and aimed into an optical cavity surrounding the cold cell to enhance the absorption signals. The comb contained about 1000 “teeth” at optical frequencies spanning the full band of buckyball vibrations. The comb light was generated from a single fiber laser.

Here’s a link to and a citation for the paper,

Rovibrational quantum state resolution of the C60 fullerene by P. Bryan Changala, Marissa L. Weichman, Kevin F. Lee, Martin E. Fermann, Jun Ye1. Science 04 Jan 2019: Vol. 363, Issue 6422, pp. 49-54 DOI: 10.1126/science.aav2616

This paper appears to be open access.

Nanoparticle ‘caterpillars’ and immune system ‘crows’

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This University of Colorado work fits in nicely with other efforts to ensure that nanoparticle medical delivery systems get to their destinations. From a Dec. 19, 2016 news item on phys.org,

In the lab, doctors can attach chemotherapy to nanoparticles that target tumors, and can use nanoparticles to enhance imaging with MRI, PET and CT scans. Unfortunately, nanoparticles look a lot like pathogens – introducing nanoparticles to the human body can lead to immune system activation in which, at best, nanoparticles are cleared before accomplishing their purpose, and at worst, the onset of dangerous allergic reaction. A University of Colorado Cancer Center paper published today [Dec. 19, 2016] in the journal Nature Nanotechnology details how the immune system recognizes nanoparticles, potentially paving the way to counteract or avoid this detection.

Specifically, the study worked with dextran-coated iron oxide nanoparticles, a promising and versatile class of particles used as drug-delivery vehicles and MRI contrast enhancers in many studies. As their name implies, the particles are tiny flecks of iron oxide encrusted with sugar chains.

“We used several sophisticated microscopy approaches to understand that the particles basically look like caterpillars,” says Dmitri Simberg, PhD, investigator at the CU Cancer Center and assistant professor in the Skaggs School of Pharmacy and Pharmaceutical Sciences, the paper’s senior author.

The comparison is striking: the iron oxide particle is the caterpillar’s body, which is surrounded by fine hairs of dextran.

Caption: University of Colorado Cancer Study shows how nanoparticles activate the complement system, potentially paving the way for expanded use of these technologies.
Credit: University of Colorado Cancer Center

A Dec. 19, 2016 University of Colorado news release on EurekAlert, which originated the news item, describes the work in more detail,

If Simberg’s dextran-coated iron oxide nanoparticles are caterpillars, then the immune system is a fat crow that would eat them – that is, if it can find them. In fact, the immune system has evolved for exactly this purpose – to find and “eat” foreign particles – and rather than one homogenous entity is actually composed of a handful of interrelated systems, each specialized to counteract a specific form of invading particle.

Simberg’s previous work shows that it is the immune subcomponent called the complement system that most challenges nanoparticles. Basically, the complement system is a group of just over 30 proteins that circulate through the blood and attach to invading particles and pathogens. In humans, complement system activation requires that three proteins come together on a particle -C3b, Bb and properdin – which form a stable complex called C3-convertase.

“The whole complement system activation starts with the assembly of C3-convertase,” Simberg says. “In this paper, we ask the question of how the complement proteins actually recognize the nanoparticle surface. How is this whole reaction triggered?”

First, it was clear that the dextran coating that was supposed to protect the nanoparticles from human complement attack was not doing its job. Simberg and colleagues could see complement proteins literally invade the barrier of dextran hairs.

“Electron microscopy images show protein getting inside the particle to touch the iron oxide core,” Simberg says.

In fact, as long as the nanoparticle coating allowed the nanoparticle to absorb proteins from blood, the C3 convertase was assembled and activated on these proteins. The composition of the coating was irrelevant – if any blood protein was able to bind to nanoparticles, it always led to complement activation. Moreover, Simberg and colleagues also showed that complement system activation is a dynamic and ongoing process – blood proteins and C3 convertase constantly dissociate from nanoparticles, and new proteins and C3 convertases bind to the particles, continuing the cascade of immune system activation. The group also demonstrated that this dynamic assembly of complement proteins occurs not only in the test tubes but also in living organisms as particles circulate in blood.

Simberg suggests that the work points to challenges and three possible strategies to avoid complement system activation by nanoparticles: “First, we could try to change the nanoparticle coating so that it can’t absorb proteins, which is a difficult task; second, we could better understand the composition of proteins absorbed from blood on the particle surface that allow it to bind complement proteins; and third, there are natural inhibitors of complement activation – for example blood Factor H – but in the context of nanoparticles, it’s not strong enough to stop complement activation. Perhaps we could get nanoparticles to attract more Factor H to decrease this activation.”

At one point, the concept of nanomedicine seemed as if it would be simple – engineers and chemists would make a nanoparticle with affinity for tumor tissue and then attach a drug molecule to it. Or they would inject nanoparticles into patients that would improve the resolution of diagnostic imaging. When the realities associated with the use of nanoparticles in the landscape of the human immune system proved more challenging, many researchers realized the need to step back from possible clinical use to better understand the mechanisms that challenge nanoparticle use.

“This basic groundwork is absolutely necessary,” says Seyed Moein Moghimi, PhD, nanotechnologist at Durham University, UK, and the coauthor of the Simberg paper. “It’s essential that we learn to control the process of immune recognition so that we can bridge between the promise that nanoparticles demonstrate in the lab and their use with real patients in the real world.”

Here’s a link to and a citation for the paper,

Complement proteins bind to nanoparticle protein corona and undergo dynamic exchange in vivo by Fangfang Chen, Guankui Wang, James I. Griffin, Barbara Brenneman, Nirmal K. Banda, V. Michael Holers, Donald S. Backos, LinPing Wu, Seyed Moein Moghimi, & Dmitri Simberg. Nature Nanotechnology  (2016) doi:10.1038/nnano.2016.269 19 December 2016

This paper is behind a paywall.

I have a few previous postings about nanoparticles as drug delivery systems which have yet to fulfill their promise. There’s the April 27, 2016 posting (How many nanoparticle-based drugs does it take to kill a cancer tumour? More than 1%) and the Sept. 9, 2016 posting (Discovering how the liver prevents nanoparticles from reaching cancer cells).

Nanoavalanches in glass

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An Aug. 24, 2016 news item on Nanowerk takes a rather roundabout way to describe some new findings about glass (Note: A link has been removed),

The main purpose of McLaren’s exchange study in Marburg was to learn more about a complex process involving transformations in glass that occur under intense electrical and thermal conditions. New understanding of these mechanisms could lead the way to more energy-efficient glass manufacturing, and even glass supercapacitors that leapfrog the performance of batteries now used for electric cars and solar energy.

“This technology is relevant to companies seeking the next wave of portable, reliable energy,” said Himanshu Jain, McLaren’s advisor and the T. L. Diamond Distinguished Chair in Materials Science and Engineering at Lehigh and director of its International Materials Institute for New Functionality in Glass. “A breakthrough in the use of glass for power storage could unleash a torrent of innovation in the transportation and energy sectors, and even support efforts to curb global warming.”

As part of his doctoral research, McLaren discovered that applying a direct current field across glass reduced its melting temperature. In their experiments, they placed a block of glass between a cathode and anode, and then exerted steady pressure on the glass while gradually heating it. McLaren and Jain, together with colleagues at the University of Colorado, published their discovery in Applied Physics Letters (“Electric field-induced softening of alkali silicate glasses”).

The implications for the finding were intriguing. In addition to making glass formulation viable at lower temperatures and reducing energy needs, designers using electrical current in glass manufacturing would have a tool to make precise manipulations not possible with heat alone.

“You could make a mask for the glass, for example, and apply an electrical field on a micron scale,” said Jain. “This would allow you to deform the glass with high precision, and soften it in a far more selective way than you could with heat, which gets distributed throughout the glass.”

Though McLaren and Jain had isolated the phenomenon and determined how to dial up the variables for optimal results, they did not yet fully understand the mechanisms behind it. McLaren and Jain had been following the work of Dr. Bernard Roling at the University of Marburg, who had discovered some remarkable characteristics of glass using electro-thermal poling, a technique that employs both temperature manipulation and electrical current to create a charge in normally inert glass. The process imparts useful optical and even bioactive qualities to glass.

Roling invited McLaren to spend a semester at Marburg to analyze the behavior of glass under electro-thermal poling, to see if it would reveal more about the fundamental science underlying what McLaren and Jain had observed in their Lehigh lab.

An Aug. 22, 2016 Lehigh University news release by Chris Quirk, which originated the news item, describes the latest work,

McLaren’s work in Marburg revealed a two-step process in which a thin sliver of the glass nearest the anode, called a depletion layer, becomes much more resistant to electrical current than the rest of the glass as alkali ions in the glass migrate away. This is followed by a catastrophic change in the layer, known as dielectric breakdown, which dramatically increases its conductivity. McLaren likens the process of dielectric breakdown to a high-speed avalanche, and uses spectroscopic analysis with electro-thermal poling as a way to see what is happening in slow motion.

“The results in Germany gave us a very good model for what is going on in the electric field-induced softening that we did here. It told us about the start conditions for where dielectric breakdown can begin,” said McLaren.

“Charlie’s work in Marburg has helped us see the kinetics of the process,” Jain said. “We could see it happening abruptly in our experiments here at Lehigh, but we now have a way to separate out what occurs specifically with the depletion layer.”

…

“The Marburg trip was incredibly useful professionally and enlightening personally,” said McLaren. “Scientifically, it’s always good to see your work from another vantage point, and see how other research groups interpret data or perform experiments. The group in Marburg was extremely hard-working, which I loved, and they were very supportive of each other. If someone submitted a paper, the whole group would have a barbecue to celebrate, and they always gave each other feedback on their work. Sometimes it was brutally honest––they didn’t hold back––but they were things you needed to hear.”

“Working in Marburg also showed me how to interact with a completely different group of people. “You see differences in your own culture best when you have the chance to see other cultures close up. It’s always a fresh perspective.”

Here are links and citations for both the papers mentioned. The first link is for the most recent paper and second link is for the earlier work,

Depletion Layer Formation in Alkali Silicate Glasses by
Electro-Thermal Poling by C. McLaren, M. Balabajew, M. Gellert, B. Roling, and H. Jain. Journal of The Electrochemical Society, 163 (9) H809-H817 (2016) H809 DOI: 10.1149/2.0881609jes Published July 19, 2016

Electric field-induced softening of alkali silicate glasses by C. McLaren, W. Heffner, R. Tessarollo, R. Raj, and H. Jain. Appl. Phys. Lett. 107, 184101 (2015); http://dx.doi.org/10.1063/1.4934945 Published online 03 November 2015

The most recent paper (first link) appears to be open access; the earlier paper (second link) is behind a paywall.

Some Baba Brinkman rap videos for Christmas

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It’s about time to catch up with Canadian rapper, Baba Brinkman who has made an industry of rapping about science issues (mostly). Here’s a brief rundown of some of his latest ventures.

He was in Paris for the climate talks (also known as World Climate Change Conference 2015 [COP21]) and produced this ‘live’ rap on Dec. 10, 2015 for the press conference on “Moral Obligation – Scientific Imperative” for Climate Matters,

The piece is part of his forthcoming album and show “The Rap Guide to Climate Chaos.”

On Dec. 18, 2015 Baba released a new music video with his take on religion and science (from a Dec. 18, 2015 posting on his blog),

The digital animation is by Steven Fahey, who is a full time animator for the Simpsons, and I’m completely blown away by the results he achieved. The video is about the evolution of religious instincts, and how the secular among us can make sense of beliefs we don’t share.

Here’s the ‘Religion evolves’ video,

A few days after Baba released his video, new research was published contradicting some of what he has in there (i.e., religion as a binding element for societies struggling to survive in ancient times. From a Dec. 21, 2015 University of Central Florida news release on EurekAlert (Note: A link has been removed),

Humans haven’t learned much in more than 2,000 years when it comes to religion and politics.

Religion has led to social tension and conflict, not just in today’s society, but dating back to 700 B.C. according to a new study published today in Current Anthropology .

University of Colorado anthropology Professor Arthur A. Joyce and University of Central Florida Associate Professor Sarah Barber found evidence in several Mexican archeological sites that contradict the long-held belief that religion acted to unite early state societies. It often had the opposite effect, the study says.

“It doesn’t matter if we today don’t share particular religious beliefs, but when people in the past acted on their beliefs, those actions could have real, material consequences,” Barber said about the team’s findings. “It really behooves us to acknowledge religion when considering political processes.”

Sounds like sage advice in today’s world that has multiple examples of politics and religion intersecting and resulting in conflict.

The team published its findings “Ensoulment, Entrapment, and Political Centralization: A Comparative Study of Religion and Politics in Later Formative Oaxaca,” after spending several years conducting field research in the lower Río Verde valley of Oaxaca, Mexico’s Pacific coastal lowlands. They compared their results with data from the highland Valley of Oaxaca.

Their study viewed archaeological evidence from 700 B.C. to A.D. 250, a period identified as a time of the emergence of states in the region. In the lower Verde, religious rituals involving offerings and the burial of people in cemeteries at smaller communities created strong ties to the local community that impeded the creation of state institutions.

And in the Valley of Oaxaca, elites became central to mediating between their communities and the gods, which eventually triggered conflict with traditional community leaders. It culminated in the emergence of a regional state with its capital at the hilltop city of Monte Albán.

“In both the Valley of Oaxaca and the Lower Río Verde Valley, religion was important in the formation and history of early cities and states, but in vastly different ways,” said Joyce, lead author on the study. “Given the role of religion in social life and politics today, that shouldn’t be too surprising.”

The conflict in the lower Río Verde valley is evident in rapid rise and fall of its state institutions. At Río Viejo, the capital of the lower Verde state, people had built massive temples by AD 100. Yet these impressive, labor-intensive buildings, along with many towns throughout the valley, were abandoned a little over a century later.

“An innovative aspect of our research is to view the burials of ancestors and ceremonial offerings in the lower Verde as essential to these ancient communities,” said Joyce, whose research focuses on both political life and ecology in ancient Mesoamerica. “Such a perspective is also more consistent with the worldviews of the Native Americans that lived there.”

Here’s a link to and a citation for the paper,

Ensoulment, Entrapment, and Political Centralization A Comparative Study of Religion and Politics in Later Formative Oaxaca by Arthur A. Joyce and Sarah B. Barber. Current Anthropology Vol. 56, No. 6 (December 2015), pp. 819-847 DOI: 10.1086/683998

This paper is behind a paywall.

Getting back to Baba, having research, which contradicts or appears to contradict your position, suddenly appear is part of the scientific process. Making your work scientifically authentic adds pressure for a performer or artist, on the other hand, it also blesses that performer or artist with credibility. In any event, it’s well worth checking out Baba’s website and, for anyone, who’s wanted to become a patron of the arts (or of a particular rapper), there’s this Dec. 3, 2015 posting on Baba’s blog about Patreon,

Every year or so since 2010 I’ve reached out to my friends and fans asking for help with a Kickstarter or IndieGogo campaign to fund my latest album or video project. Well now I’m hoping to put an end to that regular cycle with the help of Patreon, a site that lets fans become patrons with exclusive access to the artists they support and the work they help create.

Click here to visit Patreon.com/BabaBrinkman

…

Good luck Baba. (BTW, Currently living in New York with his scientist wife and child, he’s originally from the Canadian province of British Columbia.)

On the verge of controlling neurons by wireless?

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Scientists have controlled a mouse’s neurons with a wireless device (and unleashed some paranoid fantasies? well, mine if no one else’s) according to a July 16, 2015 news item on Nanowerk (Note: A link has been removed),

A study showed that scientists can wirelessly determine the path a mouse walks with a press of a button. Researchers at the Washington University School of Medicine, St. Louis, and University of Illinois, Urbana-Champaign, created a remote controlled, next-generation tissue implant that allows neuroscientists to inject drugs and shine lights on neurons deep inside the brains of mice. The revolutionary device is described online in the journal Cell (“Wireless Optofluidic Systems for Programmable In Vivo Pharmacology and Optogenetics”). Its development was partially funded by the [US] National Institutes of Health [NIH].

The researchers have made an image/illustration of the probe available,

Mind Bending Probe Scientists used soft materials to create a brain implant a tenth the width of a human hair that can wirelessly control neurons with lights and drugs. Courtesy of Jeong lab, University of Colorado Boulder.

A July 16, 2015 US NIH National Institute of Neurological Disorders and Stroke news release, which originated the news item, describes the study and notes that instructions for building the implant are included in the published study,

“It unplugs a world of possibilities for scientists to learn how brain circuits work in a more natural setting.” said Michael R. Bruchas, Ph.D., associate professor of anesthesiology and neurobiology at Washington University School of Medicine and a senior author of the study.

The Bruchas lab studies circuits that control a variety of disorders including stress, depression, addiction, and pain. Typically, scientists who study these circuits have to choose between injecting drugs through bulky metal tubes and delivering lights through fiber optic cables. Both options require surgery that can damage parts of the brain and introduce experimental conditions that hinder animals’ natural movements.

To address these issues, Jae-Woong Jeong, Ph.D., a bioengineer formerly at the University of Illinois at Urbana-Champaign, worked with Jordan G. McCall, Ph.D., a graduate student in the Bruchas lab, to construct a remote controlled, optofluidic implant. The device is made out of soft materials that are a tenth the diameter of a human hair and can simultaneously deliver drugs and lights.

“We used powerful nano-manufacturing strategies to fabricate an implant that lets us penetrate deep inside the brain with minimal damage,” said John A. Rogers, Ph.D., professor of materials science and engineering, University of Illinois at Urbana-Champaign and a senior author. “Ultra-miniaturized devices like this have tremendous potential for science and medicine.”

With a thickness of 80 micrometers and a width of 500 micrometers, the optofluidic implant is thinner than the metal tubes, or cannulas, scientists typically use to inject drugs. When the scientists compared the implant with a typical cannula they found that the implant damaged and displaced much less brain tissue.

The scientists tested the device’s drug delivery potential by surgically placing it into the brains of mice. In some experiments, they showed that they could precisely map circuits by using the implant to inject viruses that label cells with genetic dyes. In other experiments, they made mice walk in circles by injecting a drug that mimics morphine into the ventral tegmental area (VTA), a region that controls motivation and addiction.

The researchers also tested the device’s combined light and drug delivery potential when they made mice that have light-sensitive VTA neurons stay on one side of a cage by commanding the implant to shine laser pulses on the cells. The mice lost the preference when the scientists directed the device to simultaneously inject a drug that blocks neuronal communication. In all of the experiments, the mice were about three feet away from the command antenna.

“This is the kind of revolutionary tool development that neuroscientists need to map out brain circuit activity,” said James Gnadt, Ph.D., program director at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS).  “It’s in line with the goals of the NIH’s BRAIN Initiative.”

The researchers fabricated the implant using semi-conductor computer chip manufacturing techniques. It has room for up to four drugs and has four microscale inorganic light-emitting diodes. They installed an expandable material at the bottom of the drug reservoirs to control delivery. When the temperature on an electric heater beneath the reservoir rose then the bottom rapidly expanded and pushed the drug out into the brain.

“We tried at least 30 different prototypes before one finally worked,” said Dr. McCall.

“This was truly an interdisciplinary effort,” said Dr. Jeong, who is now an assistant professor of electrical, computer, and energy engineering at University of Colorado Boulder. “We tried to engineer the implant to meet some of neurosciences greatest unmet needs.”

In the study, the scientists provide detailed instructions for manufacturing the implant.

“A tool is only good if it’s used,” said Dr. Bruchas. “We believe an open, crowdsourcing approach to neuroscience is a great way to understand normal and healthy brain circuitry.”

Here’s a link to and a citation for the paper,

Wireless Optofluidic Systems for Programmable In Vivo Pharmacology and Optogenetics by Jae-Woong Jeong, Jordan G. McCall, Gunchul Shin, Yihui Zhang, Ream Al-Hasani, Minku Kim, Shuo Li, Joo Yong Sim, Kyung-In Jang, Yan Shi, Daniel Y. Hong, Yuhao Liu, Gavin P. Schmitz, Li Xia, Zhubin He, Paul Gamble, Wilson Z. Ray, Yonggang Huang, Michael R. Bruchas, and John A. Rogers.  Cell, July 16, 2015. DOI: 10.1016/j.cell.2015.06.058

This paper is behind a paywall.

I last wrote about wireless activation of neurons in a May 28, 2014 posting which featured research at the University of Massachusetts Medical School.

Ballooning with carbon nanotubes on behalf of climate science

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What a gorgeous picture!

Scientific balloon launched from New Mexico in September 2013 carrying an experimental instrument designed to collect and measure the energy of light emitted by the Sun, with the help of NIST chips coated with carbon nanotubes. Credit: LASP

Scientific balloon launched from New Mexico in September 2013 carrying an experimental instrument designed to collect and measure the energy of light emitted by the Sun, with the help of NIST chips coated with carbon nanotubes.
Credit: LASP

US National Institute of Standards and Technology (NIST) researchers made the carbon nanotube chips which help the instruments in the pictured balloon (above) to collect data about light. From the Oct. 24, 2013 news item on Nanowerk,,

A huge plastic balloon floated high in the skies over New Mexico on Sept. 29, 2013, carrying instruments to collect climate-related test data with the help of carbon nanotube chips made by the National Institute of Standards and Technology (NIST).

The onboard instrument was an experimental spectrometer designed to collect and measure visible and infrared wavelengths of light ranging from 350 to 2,300 nanometers. Simpler, lighter and less expensive than conventional counterparts, the spectrometer was tested to determine how accurately it can measure the relative energy of light emitted by the Sun and subsequently reflected or scattered by the Earth and Moon.

The Oct. 22, 2013 NIST news release, which originated the news item, provides some additional detail (Note: Footnotes have been removed),

Researchers at NIST’s Boulder, Colo., campus made the spectrometer’s “slit,” a high-precision chip that selected the entering light. The device was made under a recent agreement between NIST and the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics (LASP). The slit was then calibrated at NIST’s Gaithersburg, Md., headquarters.

For nearly a decade, NIST Boulder researchers have been using carbon nanotubes, the darkest material on Earth, to make coatings for laser power detectors. Nanotubes efficiently absorb nearly all light across a broad span of wavelengths, a useful feature for reducing internal scatter in the balloon imager. NIST also has facilities for, and expertise in, pairing nanotubes with micromachined silicon chips.

The Oct. 1, 2013 LASP (University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics) news release about the project offers information about the climate change data the researchers are hoping to collect and about the spectrometer being used for that purpose,

The instrument, funded by a $4.7 million NASA Earth Science Technology Office Instrument Incubator Program contract, is intended to acquire extremely accurate radiometric measurements of Earth relative to the incident sunlight. Over time, such measurements can tell scientists about changes in land-use, vegetation, urban landscape use, and atmospheric conditions on our planet. Such long-term radiometric measurements from the HyperSpectral Imager for Climate Science (HySICS) instrument can then help scientists identify the drivers of climate change.

Greg Kopp, HySICS Principal Investigator and CU-LASP research scientist, said, “HySICS allows us to acquire an accurate baseline of current Earth conditions so that we can monitor changes that are so relevant to society. This high altitude balloon flight was the first of two to demonstrate the instrument’s potential space capabilities needed to extend the measurements around the globe and over longer times.”

The instrument relies on precise measurements of the Sun for on-orbit calibrations. These solar measurements provide calibrations of the Earth measurements against this well-measured solar reference that other high accuracy space assets provide. Based on accurate solar calibrations, the HySICS radiometric measurements of the Earth can thus establish a long-term data record that is ten times more accurate than any current measurements.

For anyone interested in a more technical description of the device, the NIST news release has this,

For the balloon spectrometer, known as HySICS (HyperSpectral Imager for Climate Science), NIST made two types of custom chips that were stacked together in a sandwich. In the middle were aperture chips, coated with aluminum to block light transmission through the silicon, with small rectangular openings etched into the chip to allow light into the instrument.

A precision spectrometer must ensure that it only gathers light coming directly from its target, so the two outer layers of the sandwich were masking chips—larger openings etched at an angle and coated with tall, thin carbon nanotubes. These VANTAs (“vertically aligned nanotube arrays”) act as superefficient sponges to absorb scattered or stray light across the entire spectral range of the Sun.

While the balloon was in flight, the spectrometer scanned the slit across the Sun to measure solar irradiance. Spectral filters were calibrated by scanning the slit across the Moon and making measurements with and without filters in the beam path. The spectrometer also imaged light emitted from the Earth using the Sun as a reference light source.

For the information junkies amongst us, the Oct. 22, 2013 NIST news release offers links to more information about carbon nanotubes, etc. while the Oct. 1, 2013 LASP news release offers contact information for lead researcher, Greg Kopp.

The science of offering science advice—a confusing plethora

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There’s a big fuss being made about the upcoming changeover from one chief science *advisor (John Beddington) to another (Mark Walport) to the UK government with ‘advice’ and commentary being offered in the Guardian newspaper and in the journal Nature and likely elsewhere.

Roger Pielke Jr. , professor of environmental studies in the Centre for Science and Technology Policy Research at the University of Colorado (US) and author of The Honest Broker: Making Sense of Science in Policy and Politics, has written a ‘letter’ to Walport in his Apr. 15, 2013 posting on the Guardian science blogs (Note: Links have been removed),

Congratulations Dr Walport on your appointment as the UK government’s chief scientific *adviser. You join a select group. Since the position of chief science adviser was established in the US in 1957 and in the UK in 1964, fewer than 30 men (yes, all men) have occupied the position. [emphasis mine] Today across Europe, only Ireland, the Czech Republic and the European Commission have formal equivalents, which also exist in Australia, New Zealand, and soon perhaps in Japan and at the United Nations. [Scotland has a chief science *adviser; Korea has a special *Advisor for Science and Technology to the President of South Korea and that advisor, as of Oct. 2011, was professor Hyun-Ku Rhee]

In the United States, the science adviser is an assistant to the president with the formal title of Director of the Office of Science and Technology Policy. All US science advisers (except notably the first, James Killian, who had a background in public administration) have been trained in some area of physics, reflecting the cold war origins of the position. [emphases mine]

Pielke goes on to describe the science adviser mythology in the US. Apparently extraordinary access to the US president and the notion that scientific advice will be given more weight than other types of advice form the cornerstones of the mythology. The reality is somewhat different as Pielke notes,

Despite such expectations, the science adviser is an adviser just like any other in government, with a limited portfolio of responsibilities and expectations for accountability. Science advisers are not superheroes with special access and supra-political authority. Making effective use of the position within government requires the scientific community to realistically calibrate their expectations for the role.

He does outline some specific roles (the fourth was bit of a surprise to me)

Budget champion. The science adviser is a coordinator, and at times, a champion for research funding across the federal government.

Issue expert. The science adviser has a unique ability to assemble expertise to address specialised or cross-cutting policy issues.

Options Czar. The science adviser may also serve as what I have called an “honest broker of policy options”, helping the president or prime minister to understand the scope of available choice on a particular topic.

Institution builder. A fourth role is to oversee the institutionalisation of scientific advice across government. The provision of useful advice requires a commitment from policymakers to the use of evidence, but also to the creation and maintenance of strong institutions. The science adviser has a crucial role to ensure institutional integrity by providing advice on advice. [emphasis mine]

Taking into account that fourth option and this final paragraph, I have a question,

The UK has more than its fair share of this expertise, which I encourage you to take full advantage of during your tenure. These experts can provide you with much useful advice on advice. [emphasis mine] Just as there are calls for policymaking across government to be more evidence-based, so too should science and technology policy.

Has Pielke been reading Frank Herbert’s Dune? This business about “advice on advice” reminds me of a writing device Herbert used “the feint within the feint within the feint.”  Herbert, of course, was suggesting that there was layer upon layer of meaning and strategy within all exchanges. It seems to me Pielke is either suggesting that there are already layer upon layer of meaning and strategy within the business of being a science *advisor or, perhaps, he’d like to add those layers.

I gather the Walport appointment was announced well in advance as Colin Macilwain wrote an Aug. 28, 2012 essay, with a radically different perspective about the appointment and the situation regarding chief science advisers in the UK, for Nature,

The position of scientific adviser wasn’t set up to secure science budgets or communicate government policies to the public. Instead, advisers were meant to address competitiveness by bridging the great divide between what UK physicist C. P. Snow called the “two cultures”: scientists and engineers on the one hand, and the non-technical elites who govern London and Washington DC, on the other.  [emphasis mine]

It was the launch of Sputnik that led US President Dwight Eisenhower to appoint James Killian as his country’s first scientific adviser, in 1957. Seven years later, Harold Wilson was elected UK prime minister after pledging that a new Britain would be “forged in the white heat” of scientific and technological revolution. He appointed his first scientific adviser, Solly Zuckerman, in the same year.

Neither Eisenhower nor Wilson hired a scientific adviser so that their countries’ researchers could win more Nobel prizes or publish more papers. What they meant by ‘science’ was military and industrial competitiveness achieved by harnessing science and technology. …

Unfortunately, in both countries, the scientific adviser’s role has evolved in ways that marginalize its impact on competitiveness. …

I have read C. P. Snow’s essay where two cultures are mentioned and while he notes many versions of  ‘two cultures’ notably the ‘developed and developing’ worlds and ‘science and the arts’, I don’t recall anything about government and scientists. Still, Macilwain’s essay provides a contrast to Pielke’s take on science *advisor positions.

One last thing about science *advisers, the City of Southampton appointed their own in Aug. 2012, as per David Bruggeman’s Aug. 9, 2012 posting on his Pasco Phronesis blog (Note: Links have been removed),

The U.K. local council for Southampton has announced the appointment of a chief scientific adviser.  Professor AbuBakr Bahaj is the first person to hold the post, and is Professor of Sustainable Energy at Southampton University.  Southampton is a major port city on the southern coast, and part of a major urban area of over a million people.

The City Council, in announcing the appointment, describes the position of science adviser as a “role to champion science and engineering as a key driver of the economy and ensure the city uses science effectively in all policy-making.”  [emphasis mine] Perhaps based on Professor Bahaj’s background, his first projects will involve energy efficiency in city buildings and services.  To emphasize the partnership with Southampton University, the City Council leader will sit on two university panels concerned with research.

Note that the City if Southampton hies to the original impulse behind the ‘chief scientific adviser’ position. I did check the city website (Southampton City Council) today (Apr. 15, 2013) and was not able to find any further information about the position. They do not have seem to have created a webpage devoted to their Chief Science Adviser nor is there mention of the position on Professor AbuBakr Bahaj’s University of Southampton webpage.

Professor Bahaj did write about his hopes for the position in an Aug. 9, 2012 posting (on the one of the Guardian blogs) about being appointed as Chief Science Adviser for the city of Southampton (Note: A link has been removed),

The role of a city CSA [Chief Science Adviser] is not only to provide advice in addressing the above challenges, but also to establish city- and region-wide networks that will create new mechanisms to support local authorities and its communities.

Today about 51% of the world’s population live in cities, which occupy about 2% of land mass yet consume approximately 80% of the global resources. The world population is projected to grow to 9 billion by 2050 from its current estimate of 7 billion. Such an increase will undoubtedly affect the urban areas of the world, requiring new thinking in how cities could adapt to such population growth.

As for *advisor/*adviser, I tend to write advisor but both spellings are perfectly fine as per Wicktionary [advisor],

In general, adviser and advisor are interchangeable. However, adviser is used more generally to mean someone who is giving advice (what they are doing), whereas advisor is more commonly used when it means the primary role (what they are), such as job title, etc.

In the UK, Ireland and Asia the spelling is traditionally adviser, though US spelling advisor is becoming increasingly common …

For some reason, I just couldn’t make up my mind as to which spelling to use today.