Tag Archives: Bo Yu

Harvesting bioenergy to cure wounds and control weight

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I’m always a sucker for bioenergy harvesting stories but this is the first time I’ve seen research on the topic which combines weight control with wound healing. From a January 17, 2019 news item on Nanowerk,


Although electrical stimulation has therapeutic potential for various disorders and conditions, ungainly power sources have hampered practical applications. Now bioengineers have developed implantable and wearable nanogenerators from special materials that create electrical pulses when compressed by body motions. The pulses controlled weight gain and enhanced healing of skin wounds in rat models.

The work was performed by a research team led by Xudong Wang, Ph.D., Professor of Material Sciences and Engineering, College of Engineering, University of Wisconsin-Madison, and supported by the [US Dept. of Health, National Institutes of Health] National Institute of Biomedical Imaging and Bioengineering (NIBIB).

A January 17, 2019 NIBIB news release, which originated the news item, provides more technical information (Note: Links have been removed),

The researchers used what are known as piezoelectric and dielectric materials, including ceramics and crystals, which have a special property of creating an electrical charge in response to mechanical stress.

“Wang and colleagues have engineered solutions to a number of technical hurdles to create piezoelectric and dielectric materials that are compatible with body tissues and can generate a reliable, self-sufficient power supply. Their meticulous work has enabled a simple and elegant technology that offers the possibility of developing electrical stimulation therapies for a number of major diseases that currently lack adequate treatments,” explained David Rampulla, Ph.D., director of the Program in Biomaterials and Biomolecular Constructs at NIBIB

Shedding weight by curbing appetite

Worldwide, more than 700 million people — over 100 million of them children — are obese, causing health problems such as cardiovascular disease, diabetes, kidney disease, and certain cancers. In 2015 approximately four million people died of obesity-related causes1.

To address this crisis, Wang and his colleagues developed a vagal nerve stimulator (VNS) that dramatically improves appetite suppression through electrical stimulation of the vagus nerve. The approach is a promising one that has previously not proven practical because patients must carry bulky battery packs that require proper programming, and frequent recharging

The VNS consists of a small patch, about the size of a fingernail, which carries tiny devices called nanogenerators. Minimally invasive surgery was used to attach the VNS to the stomachs of rats. The rat’s stomach movements resulted in the delivery of gentle electrical pulses to the vagus nerve, which links the brain to the stomach. With the VNS, when the stomach moved in response to eating, the electric signal told the brain that the stomach was full, even if only a small amount of food was consumed.

The device curbed the rat’s appetite and reduced body weight by a remarkable 40 percent. “The stimulation is a natural response to regulate food intake, so there are no unwanted side effects,” explained Wang. When the device was removed the rats resumed their normal eating patterns and their weight returned to pre-treatment levels.

“Given the simplicity and effectiveness of the system, coupled with the fact that the effect is reversible and carries no side-effects, we are now planning testing in larger animals with the hope of eventually moving into human trials,” said Wang.

Accelerating wound healing

In another NIBIB-funded study in a rat experimental model, the researchers used their nanogenerator technology to determine whether electrical stimulation would accelerate healing of wounds on the skin surface.

For this experiment, a band of nanogenerators was placed around the rat’s chest, where the expansion from breathing created a mild electric field. Small electrodes in a bandage-like device were placed over skin wounds on the rat’s back, where they directed the electric field to cover the wound area.

The technique reduced healing times to just three days compared with nearly two weeks for the normal healing process.

Similar to the case with appetite suppression, it was known that electricity could enhance wound healing, but the devices that had been developed were large and impractical. The nanogenerator-powered bandage is completely non-invasive and produced a mild electric field that is similar to electrical activity detected in the normal wound-healing process.

The researchers observed electrical activation of normal cellular healing processes that included the movement of healthy skin fibroblasts into the wound, accompanied by the release of biochemical factors that promote the growth of the fibroblasts and other cell types that expand to repair the wound space.

“The dramatic decrease in healing time was surprising,” said Wang, “We now plan to test the device on pigs because their skin is very similar to humans.” 

The team believes the simplicity of the electric bandage will help move the technology to human trials quickly. In addition, Wang explained that the fabrication of the device is very inexpensive and a product for human use would cost about the same as a normal bandage.

The experiments on appetite suppression were reported in the December issue of Nature Communications2. The wound-healing studies were reported in the December issue of ACS Nano3. Both studies were supported by grant EB021336 from the National Institute of Biomedical Imaging and Bioengineering, and grant CA014520 from the National Cancer Institute.

Here are links to and citations for the papers,

Effective weight control via an implanted self-powered vagus nerve stimulation device by Guang Yao, Lei Kang, Jun Li, Yin Long, Hao Wei, Carolina A. Ferreira, Justin J. Jeffery, Yuan Lin, Weibo Cai & Xudong Wang. Nature Communications volume 9, Article number: 5349 (2018) DOI: https://doi.org/10.1038/s41467-018-07764-z Published 17 December 2018

Effective Wound Healing Enabled by Discrete Alternative Electric Fields from Wearable Nanogenerators by Yin Long, Hao Wei, Jun Li, Guang Yao, Bo Yu, Dalong Ni, Angela LF Gibson, Xiaoli Lan, Yadong Jiang, Weibo Cai, and Xudong Wang. ACS Nano, 2018, 12 (12), pp 12533–12540 DOI: 10.1021/acsnano.8b07038 Publication Date (Web): November 29, 2018

Copyright © 2018 American Chemical Society

Both papers are open access.

Bandage with nanogenerator promotes healing

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This bandage not only heals wounds (on rats) much faster; it’s cheap, according to a November 29, 2018 news item on Nanowerk,

A new, low-cost wound dressing developed by University of Wisconsin-Madison engineers could dramatically speed up healing in a surprising way.

The method leverages energy generated from a patient’s own body motions to apply gentle electrical pulses at the site of an injury.

In rodent tests, the dressings reduced healing times to a mere three days compared to nearly two weeks for the normal healing process.

“We were surprised to see such a fast recovery rate,” says Xudong Wang, a professor of materials science and engineering at UW-Madison. “We suspected that the devices would produce some effect, but the magnitude was much more than we expected.”

A November 29, 2018 University of Wisconsin-Madison news release (also on EurekAlert) by Sam Million-Weaver, which originated the news item, expands on the theme,

Researchers have known for several decades that electricity can be beneficial for skin healing, but most electrotherapy units in use today require bulky electrical equipment and complicated wiring to deliver powerful jolts of electricity.

“Acute and chronic wounds represent a substantial burden in healthcare worldwide,” says collaborator Angela Gibson, professor of surgery at UW-Madison and a burn surgeon and director of wound healing services at UW Health. “The use of electrical stimulation in wound healing is uncommon.”

In contrast with existing methods, the new dressing is much more straightforward.

“Our device is as convenient as a bandage you put on your skin,” says Wang.

The new dressings consist of small electrodes for the injury site that are linked to a band holding energy-harvesting units called nanogenerators, which are looped around a wearer’s torso. The natural expansion and contraction of the wearer’s ribcage during breathing powers the nanogenerators, which deliver low-intensity electric pulses.

“The nature of these electrical pulses is similar to the way the body generates an internal electric field,” says Wang.

And, those low-power pulses won’t harm healthy tissue like traditional, high-power electrotherapy devices might.

In fact, the researchers showed that exposing cells to high-energy electrical pulses caused them to produce almost five times more reactive oxygen species — major risk factors for cancer and cellular aging — than did cells that were exposed to the nanogenerators.

Also a boon to healing: They determined that the low-power pulses boosted viability for a type of skin cell called fibroblasts, and exposure to the nanogenerator’s pulses encouraged fibroblasts to line up (a crucial step in wound healing) and produce more biochemical substances that promote tissue growth.

“These findings are very exciting,” says collaborator Weibo Cai, a professor of radiology at UW-Madison. “The detailed mechanisms will still need to be elucidated in future work.”

In that vein, the researchers aim to tease out precisely how the gentle pulses aid in healing. The scientists also plan to test the devices on pig skin, which closely mimics human tissue.

And, they are working to give the nanogenerators additional capabilities–tweaking their structure to allow for energy harvesting from small imperceptible twitches in the skin or the thrumming pulse of a heartbeat.

“The impressive results in this study represent an exciting new spin on electrical stimulation for many different wound types, given the simplicity of the design,” says Gibson, who will collaborate with the team to confirm the reproducibility of these results in human skin models.

If the team is successful, the devices could help solve a major challenge for modern medicine.

“We think our nanogenerator could be the most effective electrical stimulation approach for many therapeutic purposes,” says Wang.

And because the nanogenerators consist of relatively common materials, price won’t be an issue.

“I don’t think the cost will be much more than a regular bandage,” says Wang. “The device in itself is very simple and convenient to fabricate.”

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

Effective Wound Healing Enabled by Discrete Alternative Electric Fields from Wearable Nanogenerators by Yin Long, Hao Wei, Jun Li, Guang Yao, Bo Yu, Dalong Ni, Angela LF Gibson, Xiaoli Lan, Yadong Jiang, Weibo Cai, and Xudong Wang. ACS Nano, Article ASAP DOI: 10.1021/acsnano.8b07038 Publication Date (Web): November 29, 2018

Copyright © 2018 American Chemical Society

This paper is open access.

I assume it will be a while before there are human clinical trials.

Artificial intelligence and industrial applications

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This is take on artificial intelligence that I haven’t encountered before. Sean Captain’s Nov. 15, 2016 article for Fast Company profiles industry giant GE (General Electric) and its foray into that world (Note: Links have been removed),

When you hear the term “artificial intelligence,” you may think of tech giants Amazon, Google, IBM, Microsoft, or Facebook. Industrial powerhouse General Electric is now aiming to be included on that short list. It may not have a chipper digital assistant like Cortana or Alexa. It won’t sort through selfies, but it will look through X-rays. It won’t recommend movies, but it will suggest how to care for a diesel locomotive. Today, GE announced a pair of acquisitions and new services that will bring machine learning AI to the kinds of products it’s known for, including planes, trains, X-ray machines, and power plants.

The effort started in 2015 when GE announced Predix Cloud—an online platform to network and collect data from sensors on industrial machinery such as gas turbines or windmills. At the time, GE touted the benefits of using machine learning to find patterns in sensor data that could lead to energy savings or preventative maintenance before a breakdown. Predix Cloud opened up to customers in February [2016?], but GE is still building up the AI capabilities to fulfill the promise. “We were using machine learning, but I would call it in a custom way,” says Bill Ruh, GE’s chief digital officer and CEO of its GE Digital business (GE calls its division heads CEOs). “And we hadn’t gotten to a general-purpose framework in machine learning.”

Today [Nov. 15, 2016] GE revealed the purchase of two AI companies that Ruh says will get them there. Bit Stew Systems, founded in 2005, was already doing much of what Predix Cloud promises—collecting and analyzing sensor data from power utilities, oil and gas companies, aviation, and factories. (GE Ventures has funded the company.) Customers include BC Hydro, Pacific Gas & Electric, and Scottish & Southern Energy.

The second purchase, Wise.io is a less obvious purchase. Founded by astrophysics and AI experts using machine learning to study the heavens, the company reapplied the tech to streamlining a company’s customer support systems, picking up clients like Pinterest, Twilio, and TaskRabbit. GE believes the technology will transfer yet again, to managing industrial machines. “I think by the middle of next year we will have a full machine learning stack,” says Ruh.

…

Though young, Predix is growing fast, with 270 partner companies using the platform, according to GE, which expects revenue on software and services to grow over 25% this year, to more than $7 billion. Ruh calls Predix a “significant part” of that extra money. And he’s ready to brag, taking a jab at IBM Watson for being a “general-purpose” machine-learning provider without the deep knowledge of the industries it serves. “We have domain algorithms, on machine learning, that’ll know what a power plant is and all the depth of that, that a general-purpose machine learning will never really understand,” he says.

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One especially dull-sounding new Predix service—Predictive Corrosion Management—touches on a very hot political issue: giant oil and gas pipeline projects. Over 400 people have been arrested in months of protests against the Dakota Access Pipeline, which would carry crude oil from North Dakota to Illinois. The issue is very complicated, but one concern of protestors is that a pipeline rupture would contaminate drinking water for the Standing Rock Sioux reservation.

“I think absolutely this is aimed at that problem. If you look at why pipelines spill, it’s corrosion,” says Ruh. “We believe that 10 years from now, we can detect a leak before it occurs and fix it before you see it happen.” Given how political battles over pipelines drag on, 10 years might not be so long to wait.

I recommend reading the article in its entirety if you have the time. And, for those of us in British Columbia, Canada, it was a surprise to see BC Hydro on the list of customers for one of GE’s new acquisitions. As well, that business about the pipelines hits home hard given the current debates (Enbridge Northern Gateway Pipelines) here. *ETA Dec. 27, 2016: This was originally edited just prior to publication to include information about the announcement by the Trudeau cabinet approving two pipelines for TransMountain  and Enbridge respectively while rejecting the Northern Gateway pipeline (Canadian Broadcasting Corporation [CBC] online news Nov. 29, 2016).  I trust this second edit will stick.*

It seems GE is splashing out in a big way. There’s a second piece on Fast Company, a Nov. 16, 2016 article by Sean Captain (again) this time featuring a chat between an engineer and a robotic power plant,

We are entering the era of talking machines—and it’s about more than just asking Amazon’s Alexa to turn down the music. General Electric has built a digital assistant into its cloud service for managing power plants, jet engines, locomotives, and the other heavy equipment it builds. Over the internet, an engineer can ask a machine—even one hundreds of miles away—how it’s doing and what it needs. …

Voice controls are built on top of GE’s Digital Twin program, which uses sensor readings from machinery to create virtual models in cyberspace. “That model is constantly getting a stream of data, both operational and environmental,” says Colin Parris, VP at GE Software Research. “So it’s adapting itself to that type of data.” The machines live virtual lives online, allowing engineers to see how efficiently each is running and if they are wearing down.

GE partnered with Microsoft on the interface, using the Bing Speech API (the same tech powering the Cortana digital assistant), with special training on key terms like “rotor.” The twin had little trouble understanding the Mandarin Chinese accent of Bo Yu, one of the researchers who built the system; nor did it stumble on Parris’s Trinidad accent. Digital Twin will also work with Microsoft’s HoloLens mixed reality goggles, allowing someone to step into a 3D image of the equipment.

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I can’t help wondering if there are some jobs that were eliminated with this technology.