Breathable electronic skin patch developed for continuous long-term use

Scientists have developed an electronic sensor that is hypoallergenic, breathable and can be worn constantly for a week, enabling continuous, unobtrusive health monitoring.

The patch, developed by scientists at the University of Tokyo, is, according to its creators, so thin and light that the majority of users will forget they are even wearing it – a far cry from many of the weighty or uncomfortable health monitoring solutions currently available.

Designed to withstand repeated and continuous bending and stretching, the patch can be worn during a host of day-to-day activities, including sports. As a result its creators believe it could be used not only in healthcare settings, but also to monitor professional athletes.

“It will become possible to monitor patients’ vital signs without causing any stress or discomfort,” said Professor Takao Someya, from the University of Tokyo’s Graduate School of Engineering.

The patch, which is detailed in research published today in the journal Nature Nanotechnology, is a step forward due to its breathable properties, allowing it to be worn for far longer than other ultrathin patches, which are made of rubber and other similarly non-breathable materials.

It consists of an electrode made up of several nanoscale meshes, which contain a water-soluble polymer, polyvinyl alcohol (PVA) and a thin layer of gold.

The patch is applied to the skin by spraying it with a thin layer of water, which dissolves the PVA and leaves the patch able to stick to the skin. It is even designed to adhere to the minute bumps in the skin, including sweat pores and the ridges that form human fingerprints, allowing a snug fit and good long-term attachment.

Currently it has been tested on 20 study participants, who wore the patch for a week. Not one experienced any inflammation, suggesting the patch should be suitable for wide-scale medical use.

It was also successfully bent and stretched over 10,000 times without damage, and was successfully used as an electrode to record electromyogram readings, which measure the electrical activity muscles, at similar levels to standard gel electrodes.

A diagram showing how the patch adheres to the skin. Images courtesy of Someya Laboratory, 2017.

The scientists have previously developed a patch that measures blood oxygen, and decided to create this variant upon realising the significant medical need for comfortable patches that can be worn constantly for significant periods.

“We learned that devices that can be worn for a week or longer for continuous monitoring were needed for practical use in medical and sports applications,” said Someya.

While the headline use for the patch will undoubtedly be in medical settings, it is also likely to attract considerable interest in the world of professional sports, where monitoring athletes is becoming increasingly commonplace.

 

At present, most of the wearables used to monitor athletes are housed in plastic units that are temporarily attached to the skin using harnesses or pockets in sports equipment, however such a patch could enable a less obtrusive approach to monitoring.

Soviet report detailing lunar rover Lunokhod-2 released for first time

Russian space agency Roskosmos has released an unprecedented scientific report into the lunar rover Lunokhod-2 for the first time, revealing previously unknown details about the rover and how it was controlled back on Earth.

The report, written entirely in Russian, was originally penned in 1973 following the Lunokhod-2 mission, which was embarked upon in January of the same year. It had remained accessible to only a handful of experts at the space agency prior to its release today, to mark the 45th anniversary of the mission.

Bearing the names of some 55 engineers and scientists, the report details the systems that were used to both remotely control the lunar rover from a base on Earth, and capture images and data about the Moon’s surface and Lunokhod-2’s place on it. This information, and in particularly the carefully documented issues and solutions that the report carries, went on to be used in many later unmanned missions to other parts of the solar system.

As a result, it provides a unique insight into this era of space exploration and the technical challenges that scientists faced, such as the low-frame television system that functioned as the ‘eyes’ of the Earth-based rover operators.

A NASA depiction of the Lunokhod mission. Above: an image of the rover, courtesy of NASA, overlaid onto a panorama of the Moon taken by Lunokhod-2, courtesy of Ruslan Kasmin.

One detail that main be of particular interest to space enthusiasts and experts is the operation of a unique system called Seismas, which was tested for the first time in the world during the mission.

Designed to determine the precise location of the rover at any given time, the system involved transmitting information over lasers from ground-based telescopes, which was received by a photodetector onboard the lunar rover. When the laser was detected, this triggered the emission of a radio signal back to the Earth, which provided the rover’s coordinates.

Other details, while technical, also give some insight into the culture of the mission, such as the careful work to eliminate issues in the long-range radio communication system. One issue, for example, was worked on with such thoroughness that it resulted in one of the devices using more resources than it was allocated, a problem that was outlined in the report.

The document also provides insight into on-Earth technological capabilities of the time. While it is mostly typed, certain mathematical symbols have had to be written in by hand, and the report also features a number of diagrams and graphs that have been painstakingly hand-drawn.

A hand-drawn graph from the report, showing temperature changes during one of the monitoring sessions during the mission

Lunokhod-2 was the second of two unmanned lunar rovers to be landed on the Moon by the Soviet Union within the Lunokhod programme, having been delivered via a soft landing by the unmanned Luna 21 spacecraft in January 1973.

In operation between January and June of that year, the robot covered a distance of 39km, meaning it still holds the lunar distance record to this day.

One of only four rovers to be deployed on the lunar surface, Lunokhod-2 was the last rover to visit the Moon until December 2013, when Chinese lunar rover Yutu made its maiden visit.

Robot takes first steps towards building artificial lifeforms

A robot equipped with sophisticated AI has successfully simulated the creation of artificial lifeforms, in a key first step towards the eventual goal of creating true artificial life.

The robot, which was developed by scientists at the University of Glasgow, was able to model the creation of artificial lifeforms using unstable oil-in-water droplets. These droplets effectively played the role of living cells, demonstrating the potential of future research to develop living cells based on building blocks that cannot be found in nature.

Significantly, the robot also successfully predicted their properties before they were created, even though this could not be achieved using conventional physical models.

The robot, which was designed by Glasgow University’s Regius Chair of Chemistry, Professor Lee Cronin, is driven by machine learning and the principles of evolution.

It has been developed to autonomously create oil-in-water droplets with a host of different chemical makeups and then use image recognition to assess their behaviour.

Using this information, the robot was able to engineer droplets to have different properties­. Those which were found to be desirable could then be recreated at any time, using a specific digital code.

“This work is exciting as it shows that we are able to use machine learning and a novel robotic platform to understand the system in ways that cannot be done using conventional laboratory methods, including the discovery of ‘swarm’ like group behaviour of the droplets, akin to flocking birds,” said Cronin.

“Achieving lifelike behaviours such as this are important in our mission to make new lifeforms, and these droplets may be considered ‘protocells’ – simplified models of living cells.”

One of the oil droplets created by the robot

The research, which is published today in the journal PNAS, is one of several research projects being undertaken by Cronin and his team within the field of artificial lifeforms.

While the overarching goal is moving towards the creation of lifeforms using new and unprecedented building blocks, the research may also have more immediate potential applications.

The team believes that their work could also have applications in several practical areas, including the development of new methods for drug delivery or even innovative materials with functional properties.