Tag: smartphones

Texting While Walking Increases the Risk of Slipping and Falling

Photo by Azat Satlykov on Unsplash

People are increasingly glued to their smartphones, texting even as they walk, which has inspired a wide range of studies: some have shown that they can multitask and navigate around obstacles while other have shown that they are more likely to walk into traffic. But how likely are they to avoid a fall if they slip? University of New South Wales (UNSW) researchers investigated this by simulating an environment with random slipping threats, and reported in the journal Heliyon that texting increases the risk of falling in response to walkway hazards.

“On any day it seems as many as 80% of people, both younger and older, may be head down and texting. I wondered: is this safe?” says senior author Matthew A. Brodie, a neuroscientist and engineer at the UNSW Graduate School of Biomedical Engineering. “This has made me want to investigate the dangers of texting while walking. I wanted to know if these dangers are real or imagined and to measure the risk in a repeatable way.”

The team recruited 50 UNSW undergraduate students from his “Mechanics of the Human Body” course for this experiment. Brodie and co-author Yoshiro Okubo invented a tiled hazard walkway at Neuroscience Research Australia’s gait laboratory, which halfway through had a tile that could be adjusted to slide out of place and cause a person stepping on it to slip. Students wore a safety harness and sensors that collected their motion data. They then were asked to go along the walkway either without texting or while typing “The quick brown fox jumps over the lazy dog.”

To better simulate the uncertainty of real life, students were only told that they may or may not slip. This allowed the researchers to study how texting pedestrians might anticipate and try to prevent a potential slip, such as by leaning forward.

“What surprised me is how differently people responded to the threat of slipping,” says Brodie. “Some slowed down and took a more cautious approach. Others sped up in anticipation of slipping. Such different approaches reinforce how no two people are the same, and to better prevent accidents from texting while walking, multiple strategies may be needed.”

Despite motion data showing that texting participants tried to be more cautious in response to a threat, this did not counteract their risk of falling. When participants went from leaning forwards (such as over a phone) to slipping backwards, their motion sensors showed an increase in the range of their ‘trunk angle’. Researchers used this number to measure whether the texting condition was making students more likely to fall, and they found that the average trunk angle range during a fall significantly increased if a student was texting.

Walking also caused the texters’ accuracy to decrease. The highest texting accuracy occurred when participants were seated, but accuracy decreased even as walking participants were cautioned about a potential slip that did not occur. The lowest accuracy, however, occurred in conditions where participants did slip.

The researchers note that young people may be more likely to take risks even if they are aware that texting and walking could increase their likelihood of falling. For that reason, the authors suggest that educational initiatives such as signs might be less effective in reaching this population. In addition to education, the researchers also suggest that phones could implement locking technology similar to what is used when users are driving. The technology could detect walking activity and activate a screen lock to prevent texting during that time. In future research, the team plans on looking into the effectiveness of this intervention.

Source: Science Daily

A Super-cheap Smartphone Accessory for Blood Pressure Monitoring

Photo by Ivan Samkov on Pexels

Engineers have developed a simple, low-cost clip that uses a smartphone’s camera and flash to monitor blood pressure at the user’s fingertip. The clip works with a custom smartphone app and currently costs about $0.80 to make. The researchers estimate that the cost could be as low as $0.10 apiece when manufactured at scale. The technology was described in the journal Scientific Reports.

Researchers say it could help make regular blood pressure monitoring easy, affordable and accessible to people in resource-poor communities. It could benefit older adults and pregnant women, for example, in managing conditions such as hypertension.

“We’ve created an inexpensive solution to lower the barrier to blood pressure monitoring,” said study first author Yinan (Tom) Xuan, an electrical and computer engineering PhD student at University of California San Diego.

“Because of their low cost, these clips could be handed out to anyone who needs them but cannot go to a clinic regularly,” said study senior author Edward Wang, a professor of electrical and computer engineering at UC San Diego and director of the Digital Health Lab. “A blood pressure monitoring clip could be given to you at your checkup, much like how you get a pack of floss and toothbrush at your dental visit.”

Another key advantage of the clip is that it does not need to be calibrated to a cuff.

“This is what distinguishes our device from other blood pressure monitors,” said Wang. Other cuffless systems being developed for smartwatches and smartphones, he explained, require obtaining a separate set of measurements with a cuff so that their models can be tuned to fit these measurements.

“Our is a calibration-free system, meaning you can just use our device without touching another blood pressure monitor to get a trustworthy blood pressure reading.”

To measure blood pressure, the user simply presses on the clip with a fingertip. A custom smartphone app guides the user on how hard and long to press during the measurement.

The clip is a 3D-printed plastic attachment that fits over a smartphone’s camera and flash. It features an optical design similar to that of a pinhole camera. When the user presses on the clip, the smartphone’s flash lights up the fingertip. That light is then projected through a pinhole-sized channel to the camera as an image of a red circle. A spring inside the clip allows the user to press with different levels of force. The harder the user presses, the bigger the red circle appears on the camera.

The smartphone app extracts two main pieces of information from the red circle. By looking at the size of the circle, the app can measure the amount of pressure that the user’s fingertip applies. And by looking at the brightness of the circle, the app can measure the volume of blood going in and out of the fingertip. An algorithm converts this information into systolic and diastolic blood pressure readings.

The researchers tested the clip on 24 volunteers from the UC San Diego Medical Center. Results were comparable to those taken by a blood pressure cuff.

“Using a standard blood pressure cuff can be awkward to put on correctly, and this solution has the potential to make it easier for older adults to self-monitor blood pressure,” said study co-author and medical collaborator Alison Moore, chief of the Division of Geriatrics in the Department of Medicine at UC San Diego School of Medicine.

While the team has only proven the solution on a single smartphone model, the clip’s current design theoretically should work on other phone models, said Xuan.

Next steps include making the technology more user friendly, especially for older adults; testing its accuracy across different skin tones; and creating a more universal design.

Source: University of California San Diego

A New Way to Measure Blood Pressure: A Digital Camera

Male doctor with smartphone
Photo by Ivan Samkov on Unsplash

Engineers have designed a system that can remotely measure blood pressure from video of a person’s forehead and using artificial intelligence algorithms to extracting cardiac signals across a range of skin tones. They describe their new technology in a new paper published in Inventions.

Using the same remote-health technology they pioneered for non-contact monitoring of vital health signs, this new technology could replace the existing uncomfortable and cumbersome method of strapping an inflatable cuff to a patient’s arm or wrist, the researchers claim.

The researchers, from the University of South Australia and Baghdad’s Middle Technical University, describe the technique, which involves filming a person from a short distance for 10 seconds and then using AI to extract cardiac signals from two regions in the forehead.

Experiments were performed on 25 people with different skin tones and under changing light conditions, overcoming the limitations reported in previous studies. Compared to a digital sphygmomanometer (itself subject to errors), the systolic and diastolic readings were around 90% accurate.

“Monitoring blood pressure is essential to detect and manage cardiovascular diseases, the leading cause of global mortality, responsible for almost 18 million deaths in 2019,” says UniSA remote sensing engineer Professor Javaan Chahl. “Furthermore, in the past 30 years, the number of adults with hypertension has risen from 650 million to 1.28 billion worldwide.”

“The health sector needs a system that can accurately measure blood pressure and assess cardiovascular risks when physical contact with patients is unsafe or difficult, such as during the recent COVID outbreak,” Prof Chahl continues. “If we can perfect this technique, it will help manage one of the most serious health challenges facing the world today.”

The cutting-edge technology has come a long way since 2017, when the UniSA and Iraqi research team demonstrated image-processing algorithms that could extract a human’s heart rate from drone video.

In the past five years the researchers have developed algorithms to measure other vital signs, including breathing rates from 50 metres away, oxygen saturation, temperature, and jaundice in newborns.

Their non-contact technology was also deployed in the United States during the pandemic for non-contact monitoring of COVID signs.

Source: University of South Australia

Smartphones are Potential Reservoirs for Allergens

Photo by Asterfolio on Unsplash

Smartphones are nowadays ubiquitous and repeatedly checked throughout the day, making them potential receptacles for environmental hazards such as allergens. A new study being presented at this year’s American College of Allergy, Asthma and Immunology (ACAAI) Annual Scientific Meeting in Louisville, KY, showed elevated levels of cat and dog allergens, as well as β-D glucans (BDG) and endotoxin on simulated phone models.

“Smartphones showed elevated and variable levels of BDG and endotoxin, and cat and dog allergens were found on smartphones of pet owners” says Hana Ruran, lead author on the study. “BDGs are found in fungal cell walls and have been found in many environments and surfaces causing chronic airway and irritant symptoms – making BDGs a consistent marker to study problematic mould. Endotoxin is a potent inflammatory agent and a marker of exposure to Gram negative bacteria.”

The researchers created phone models that had a similar size and surface to a real phone and the front surface of the phone model was wiped as part of the test. Electrostatic wipes (ESW) were used to sample simulated phone models of 15 volunteers and the “phones” were then measured for allergens, BDG and endotoxin levels.

The chemicals used in the mixture solutions for cleaning (chlorhexidine, cetylpyridinium chloride, tannic acid and benzyl benzoate) can be purchased through laboratory or chemical suppliers but are not commercially available in the same concentrations as used in the study. Isopropyl alcohol wipes were also tested for their cleaning properties.

“Combination chlorhexidine/cetylpyridinium was the most effective in reducing BDG and endotoxin and combination benzyl benzoate/tannic acid most effectively reduced cat and dog allergens on smartphones,” says Peter Thorne, PhD, professor in the University of Iowa Department of Public Health and co-author of the study. “The study demonstrates exposure to inhalant allergens and molecules that trigger innate immune reactions from a source most people haven’t considered. If you have allergies or asthma, you may want to think about cleaning your smartphone more often to minimise exposure to these allergens and asthma triggers.”

Source: American College of Allergy, Asthma, and Immunology