Tag Archives: Zhan Zhang

Neuromorphic (brainlike) computing inspired by sea slugs

The sea slug has taught neuroscientists the intelligence features that any creature in the animal kingdom needs to survive. Now, the sea slug is teaching artificial intelligence how to use those strategies. Pictured: Aplysia californica. (Image by NOAA Monterey Bay National Marine Sanctuary/Chad King.)

I don’t think I’ve ever seen a picture of a sea slug before. Its appearance reminds me of its terrestrial cousin.

As for some of the latest news on brainlike computing, a December 7, 2021 news item on Nanowerk makes an announcement from the Argonne National Laboratory (a US Department of Energy laboratory; Note: Links have been removed),

A team of scientists has discovered a new material that points the way toward more efficient artificial intelligence hardware for everything from self-driving cars to surgical robots.

For artificial intelligence (AI) to get any smarter, it needs first to be as intelligent as one of the simplest creatures in the animal kingdom: the sea slug.

A new study has found that a material can mimic the sea slug’s most essential intelligence features. The discovery is a step toward building hardware that could help make AI more efficient and reliable for technology ranging from self-driving cars and surgical robots to social media algorithms.

The study, published in the Proceedings of the National Academy of Sciences [PNAS] (“Neuromorphic learning with Mott insulator NiO”), was conducted by a team of researchers from Purdue University, Rutgers University, the University of Georgia and the U.S. Department of Energy’s (DOE) Argonne National Laboratory. The team used the resources of the Advanced Photon Source (APS), a DOE Office of Science user facility at Argonne.

A December 6, 2021 Argonne National Laboratory news release (also on EurekAlert) by Kayla Wiles and Andre Salles, which originated the news item, provides more detail,

“Through studying sea slugs, neuroscientists discovered the hallmarks of intelligence that are fundamental to any organism’s survival,” said Shriram Ramanathan, a Purdue professor of Materials Engineering. ​“We want to take advantage of that mature intelligence in animals to accelerate the development of AI.”

Two main signs of intelligence that neuroscientists have learned from sea slugs are habituation and sensitization. Habituation is getting used to a stimulus over time, such as tuning out noises when driving the same route to work every day. Sensitization is the opposite — it’s reacting strongly to a new stimulus, like avoiding bad food from a restaurant.

AI has a really hard time learning and storing new information without overwriting information it has already learned and stored, a problem that researchers studying brain-inspired computing call the ​“stability-plasticity dilemma.” Habituation would allow AI to ​“forget” unneeded information (achieving more stability) while sensitization could help with retaining new and important information (enabling plasticity).

In this study, the researchers found a way to demonstrate both habituation and sensitization in nickel oxide, a quantum material. Quantum materials are engineered to take advantage of features available only at nature’s smallest scales, and useful for information processing. If a quantum material could reliably mimic these forms of learning, then it may be possible to build AI directly into hardware. And if AI could operate both through hardware and software, it might be able to perform more complex tasks using less energy.

“We basically emulated experiments done on sea slugs in quantum materials toward understanding how these materials can be of interest for AI,” Ramanathan said.

Neuroscience studies have shown that the sea slug demonstrates habituation when it stops withdrawing its gill as much in response to tapping. But an electric shock to its tail causes its gill to withdraw much more dramatically, showing sensitization.

For nickel oxide, the equivalent of a ​“gill withdrawal” is an increased change in electrical resistance. The researchers found that repeatedly exposing the material to hydrogen gas causes nickel oxide’s change in electrical resistance to decrease over time, but introducing a new stimulus like ozone greatly increases the change in electrical resistance.

Ramanathan and his colleagues used two experimental stations at the APS to test this theory, using X-ray absorption spectroscopy. A sample of nickel oxide was exposed to hydrogen and oxygen, and the ultrabright X-rays of the APS were used to see changes in the material at the atomic level over time.

“Nickel oxide is a relatively simple material,” said Argonne physicist Hua Zhou, a co-author on the paper who worked with the team at beamline 33-ID. ​“The goal was to use something easy to manufacture, and see if it would mimic this behavior. We looked at whether the material gained or lost a single electron after exposure to the gas.”

The research team also conducted scans at beamline 29-ID, which uses softer X-rays to probe different energy ranges. While the harder X-rays of 33-ID are more sensitive to the ​“core” electrons, those closer to the nucleus of the nickel oxide’s atoms, the softer X-rays can more readily observe the electrons on the outer shell. These are the electrons that define whether a material is conductive or resistive to electricity.

“We’re very sensitive to the change of resistivity in these samples,” said Argonne physicist Fanny Rodolakis, a co-author on the paper who led the work at beamline 29-ID. ​“We can directly probe how the electronic states of oxygen and nickel evolve under different treatments.”

Physicist Zhan Zhang and postdoctoral researcher Hui Cao, both of Argonne, contributed to the work, and are listed as co-authors on the paper. Zhang said the APS is well suited for research like this, due to its bright beam that can be tuned over different energy ranges.

For practical use of quantum materials as AI hardware, researchers will need to figure out how to apply habituation and sensitization in large-scale systems. They also would have to determine how a material could respond to stimuli while integrated into a computer chip.

This study is a starting place for guiding those next steps, the researchers said. Meanwhile, the APS is undergoing a massive upgrade that will not only increase the brightness of its beams by up to 500 times, but will allow for those beams to be focused much smaller than they are today. And this, Zhou said, will prove useful once this technology does find its way into electronic devices.

“If we want to test the properties of microelectronics,” he said, ​“the smaller beam that the upgraded APS will give us will be essential.”

In addition to the experiments performed at Purdue and Argonne, a team at Rutgers University performed detailed theory calculations to understand what was happening within nickel oxide at a microscopic level to mimic the sea slug’s intelligence features. The University of Georgia measured conductivity to further analyze the material’s behavior.

A version of this story was originally published by Purdue University

About the Advanced Photon Source

The U. S. Department of Energy Office of Science’s Advanced Photon Source (APS) at Argonne National Laboratory is one of the world’s most productive X-ray light source facilities. The APS provides high-brightness X-ray beams to a diverse community of researchers in materials science, chemistry, condensed matter physics, the life and environmental sciences, and applied research. These X-rays are ideally suited for explorations of materials and biological structures; elemental distribution; chemical, magnetic, electronic states; and a wide range of technologically important engineering systems from batteries to fuel injector sprays, all of which are the foundations of our nation’s economic, technological, and physical well-being. Each year, more than 5,000 researchers use the APS to produce over 2,000 publications detailing impactful discoveries, and solve more vital biological protein structures than users of any other X-ray light source research facility. APS scientists and engineers innovate technology that is at the heart of advancing accelerator and light-source operations. This includes the insertion devices that produce extreme-brightness X-rays prized by researchers, lenses that focus the X-rays down to a few nanometers, instrumentation that maximizes the way the X-rays interact with samples being studied, and software that gathers and manages the massive quantity of data resulting from discovery research at the APS.

This research used resources of the Advanced Photon Source, a U.S. DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.

The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://​ener​gy​.gov/​s​c​ience.

You can find the September 24, 2021 Purdue University story, Taking lessons from a sea slug, study points to better hardware for artificial intelligence here.

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

Neuromorphic learning with Mott insulator NiO by Zhen Zhang, Sandip Mondal, Subhasish Mandal, Jason M. Allred, Neda Alsadat Aghamiri, Alireza Fali, Zhan Zhang, Hua Zhou, Hui Cao, Fanny Rodolakis, Jessica L. McChesney, Qi Wang, Yifei Sun, Yohannes Abate, Kaushik Roy, Karin M. Rabe, and Shriram Ramanathan. PNAS September 28, 2021 118 (39) e2017239118 DOI: https://doi.org/10.1073/pnas.2017239118

This paper is behind a paywall.

Ginger-derived nano-lipids for colorectal cancer

Didier Merlin’s team at the US Dept. of Veteran’s Affairs along with researchers from Georgia State University and from two Chinese universities have published more research on what they are calling, GDNPs, or ginger-derived nanoparticles. (See my Sept. 8, 2016 posting for my first post about ginger nanoparticles and the US Dept. of Veterans Affairs.)

Ginger, well known for relieving nausea, may soon be able to claim another health benefit according to a Sept. 6, 2016 news item on ScienceDaily,

Edible ginger-derived nano-lipids created from a specific population of ginger nanoparticles show promise for effectively targeting and delivering chemotherapeutic drugs used to treat colon cancer, according to a study by researchers at the Institute for Biomedical Sciences at Georgia State University, the Atlanta Veterans Affairs Medical Center and Wenzhou Medical University and Southwest University in China.

A Sept. 6, 2016 Georgia State University news release (also on EurekAlert), which originated the news item, describes both the situation with colorectal cancer in the US and the research,

Colorectal cancer is the third most common cancer among men and women in the United States, and the second-leading cause of cancer-related deaths among men and women worldwide. The incidence of colorectal cancer has increased over the last few years, with about one million new cases diagnosed annually. Non-targeted chemotherapy is the most common therapeutic strategy available for colon cancer patients, but this treatment method is unable to distinguish between cancerous and healthy cells, leading to poor therapeutic effects on tumor cells and severe toxic side effects on healthy cells. Enabling chemotherapeutic drugs to target cancer cells would be a major development in the treatment of colon cancer.

In this study, the researchers isolated a specific nanoparticle population from edible ginger (GDNP 2) and reassembled their lipids, naturally occurring molecules that include fats, to form ginger-derived nano-lipids, also known as nanovectors. To achieve accurate targeting of tumor tissues, the researchers modified the nanovectors with folic acid to create FA-modified nanovectors (FA nanovectors). Folic acid shows high-affinity binding to the folate receptors that are highly expressed on many tumors and almost undetectable on non-tumor cells.

The FA nanovectors were tested as a delivery platform for doxorubicin, a chemotherapeutic drug used to treat colon cancer. The researchers found that doxorubicin was efficiently loaded into the FA nanovectors, and the FA nanovectors were efficiently taken up by colon cancer cells, exhibited excellent biocompatibility and successfully inhibited tumor growth. Compared to a commercially available option for delivering doxorubicin, the FA nanovectors released the drug more rapidly in an acidic pH that resembled the tumor environment, suggesting this delivery strategy could decrease the severe side effects of doxorubicin. These findings were published in the journal Molecular Therapy.

“Our results show that FA nanovectors made of edible ginger-derived lipids could shift the current paradigm of drug delivery away from artificially synthesized nanoparticles toward the use of nature-derived nanovectors from edible plants,” said Dr. Didier Merlin, a professor in the Institute for Biomedical Sciences at Georgia State and a Research Career Scientist at the VA Medical Center. “Because they are nontoxic and can be produced on a large scale, FA nanovectors derived from edible plants could represent one of the safest targeted therapeutic delivery platforms.”

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

Edible Ginger-derived Nano-lipids Loaded with Doxorubicin as a Novel Drug-delivery Approach for Colon Cancer Therapy by Mingzhen Zhang, Bo Xiao, Huan Wang, Moon Kwon Han, Zhan Zhang, Emilie Viennois, Changlong Xu, and Didier Merlin. Molecular Therapy (2016); doi:10.1038/mt.2016.159 Advance online publication 13 September 2016

This paper is behind a paywall.

Ginger nanoparticles for inflammatory bowel disease

I guess we’ll have to add ginger to the list of folk medicines (tumeric is another) which are being discovered by nanomedicine. An Aug. 17, 2016 news item on ScienceDaily describes the ‘ginger’ research at the US Dept. of Veterans Affairs,

A recent study by researchers at the Atlanta Veterans Affairs Medical Center took them to a not-so-likely destination: local farmers markets. They went in search of fresh ginger root.

Back at the lab, the scientists turned the ginger into what they are calling GDNPs, or ginger-derived nanoparticles. The process started simply enough, with your basic kitchen blender. But then it involved super-high-speed centrifuging and ultrasonic dispersion of the ginger juice, to break it up into single pellets. (Don’t try this at home!)

The research team, led by Dr. Didier Merlin with VA and the Institute for Biomedical Sciences at Georgia State University, believes the particles may be good medicine for Crohn’s disease and ulcerative colitis, the two main forms of inflammatory bowel disease (IBD). The particles may also help fight cancer linked to colitis, the scientists believe.

An Aug. 16, 2016 US Dept. of Veterans Affairs news release (also on EurekAlert), which originated the news item, provides more detail about the research,

Each ginger-based nanoparticle was about 230 nanometers in diameter. More than 300 of them could fit across the width of a human hair.

Fed to lab mice, the particles appeared to be nontoxic and had significant therapeutic effects:

  • Importantly, they efficiently targeted the colon. They were absorbed mainly by cells in the lining of the intestines, where IBD inflammation occurs.
  • The particles reduced acute colitis and prevented chronic colitis and colitis-associated cancer.
  • They enhanced intestinal repair. Specifically, they boosted the survival and proliferation of the cells that make up the lining of the colon. They also lowered the production of proteins that promote inflammation, and raised the levels of proteins that fight inflammation.

Part of the therapeutic effect, say the researchers, comes from the high levels of lipids–fatty molecules–in the particles, a result of the natural lipids in the ginger plant. One of the lipids is phosphatidic acid, an important building block of cell membranes.

The particles also retained key active constituents found naturally in ginger, such as 6-gingerol and 6-shogaol. Past lab studies have shown the compounds to be active against oxidation, inflammation, and cancer. They are what make standard ginger an effective remedy for nausea and other digestion problems. Traditional cultures have used ginger medicinally for centuries, and health food stores carry ginger-based supplements–such as chews, or the herb mixed with honey in a syrup–as digestive aids.

Delivering these compounds in a nanoparticle, says Merlin’s team, may be a more effective way to target colon tissue than simply providing the herb as a food or supplement.

The idea of fighting IBD with nanoparticles is not new. In recent years, Merlin’s lab and others have explored how to deliver conventional drugs via nanotechnology. Some of this research is promising. The approach may allow low doses of drugs to be delivered only where they are needed–inflamed tissue in the colon–and thus avoid unwanted systemic effects.

The advantage of ginger, say the researchers, is that it’s nontoxic, and could represent a very cost-effective source of medicine.

The group is looking at ginger, and other plants, as potential “nanofactories for the fabrication of medical nanoparticles.”

Merlin and his VA and Georgia State University coauthors elaborated on the idea in a report earlier this year titled “Plant-derived edible nanoparticles as a new therapeutic approach against diseases.” They wrote that plants are a “bio-renewable, sustainable, diversified platform for the production of therapeutic nanoparticles.”

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

Edible ginger-derived nanoparticles: A novel therapeutic approach for the prevention and treatment of inflammatory bowel disease and colitis-associated cancer by Mingzhen Zhang, Emilie Viennois, Meena Prasad, Yunchen Zhang, Lixin Wang, Zhan Zhang, Moon Kwon Han, Bo Xiao, Changlong Xu, Shanthi Srinivasan, Didier Merlin. Biomaterials Volume 101, September 2016, Pages 321–340         doi:10.1016/j.biomaterials.2016.06.018

This paper is behind a paywall.

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

Plant derived edible nanoparticles as a new therapeutic approach against diseases by Mingzhen Zhang, Emilie Viennois, Changlong Xu, & Didier Merlin. Tissue Barriers Volume 4, 2016 – Issue 2  http://dx.doi.org/10.1080/21688370.2015.1134415 Published online: 11 Feb 2016

This paper too is behind a paywall.