(Press-News.org) A research team, affiliated with UNIST, has unveiled for the first time a new principle of motion in the microworld, where objects can move in a directed manner simply by changing their sizes periodically within a substance known as liquid crystal. Led by Professor Jonwoo Jeong and his research team in the Department of Physics at UNIST, this discovery is poised to have far-reaching implications across various research fields, including the potential development of miniature robots in the future.
In their research, the team observed that air bubbles within the liquid crystal could move in one direction by altering their sizes periodically, contrary to the symmetrical growth or contraction typically seen in air bubbles in other mediums. By introducing air bubbles, comparable in size to a human hair, into the liquid crystal and manipulating the pressure, the researchers were able to demonstrate this extraordinary phenomenon.
The key to this phenomenon lies in the creation of phase defects within the liquid crystal structure next to the air bubbles. These defects disrupt the symmetrical nature of the bubbles, enabling them to experience a unidirectional force despite their symmetrical shape. As the air bubbles fluctuate in size, pushing and pulling the surrounding liquid crystal, they are propelled in a consistent direction, defying conventional laws of physics.
Sung-Jo Kim, the first author of the study, remarked, “This groundbreaking observation showcases the ability of symmetrical objects to exhibit directed motion through symmetrical movements, a phenomenon previously unseen.” He further highlighted the potential applicability of this principle to a wide range of complex fluids beyond liquid crystals.
Professor Jeong commented, “This intriguing result underscores the significance of symmetry breaking in both time and space in driving motion at the microscopic level. Moreover, it holds promise for advancing research in the development of microscopic robots.”
Their findings have been published in the online version of Nature Communications on February 9, 2024. This research has been supported by the National Research Foundation of Korea (NRF), the Institute of Basic Science (IBS), and the Slovenian Research Agency (ARRS).
Journal Reference
Sung-Jo Kim, Žiga Kos, Eujin Um, and Joonwoo Jeong, “Symmetrically pulsating bubbles swim in an anisotropic fluid by nematodynamics,” Nat. Commun., (2024).
END
UNIST researchers uncover revolutionary phenomenon in liquid crystals
2024-03-13
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
Study tracks shifts in student mental health during college
2024-03-13
A four-year study by Dartmouth researchers captures the most in-depth data yet on how college students' self-esteem and mental health fluctuates during their four years in academia, identifying key populations and stressors that the researchers say administrators could target to improve student well-being.
The study also provides among the first real-time accounts of how the coronavirus pandemic affected students' behavior and mental health. The stress and uncertainty of COVID-19 resulted in long-lasting behavioral changes that persisted as a "new normal" even as the pandemic diminished, including feeling more stressed, less socially engaged, and sleeping more.
The ...
Recreational activities such as golfing, gardening may be associated with increased ALS risk among men
2024-03-13
Participation in recreational activities — including golfing, gardening or yard work, woodworking and hunting — may be associated with an increase in a person’s risk for developing amyotrophic lateral sclerosis, or ALS, a Michigan Medicine study finds.
While many activities were associated with increased ALS risk, several were sex specific. The results are published in the Journal of the Neurological Sciences.
“We know that occupational risk factors, like working in manufacturing and trade industries, are linked to an increased risk for ALS, and this adds to a growing literature that recreational activities may also represent ...
You don’t need glue to hold these materials together — just electricity
2024-03-13
Is there a way to stick hard and soft materials together without any tape, glue or epoxy? A new study published in ACS Central Science shows that applying a small voltage to certain objects forms chemical bonds that securely link the objects together. Reversing the direction of electron flow easily separates the two materials. This electroadhesion effect could help create biohybrid robots, improve biomedical implants and enable new battery technologies.
When an adhesive is used to attach two things, it binds the surfaces either through mechanical or electrostatic forces. But sometimes those attractions or bonds are difficult, if not ...
Heart disease risk factors of modern lifestyles threaten extremely poor people living in low- and middle-income countries
2024-03-13
A new study reveals that many people living in extreme poverty in low- and middle-income countries (LMICs) have conditions that lead to heart disease, the world’s #1 cause of death — overturning ‘conventional wisdom’.
In the largest analysis of its kind exploring the relationship between poverty and cardiovascular disease (CVD) risk factors, experts discovered a high prevalence of hypertension, diabetes, smoking, obesity, and dyslipidemia in LMICs regardless of income —yet most adults living in extreme poverty were not treated for these CVD-related conditions.
An international group of researchers note that their findings, ...
Air quality in Europe shows significant improvements over the last two decades, study finds
2024-03-13
A study led by the Barcelona Institute for Global Health (ISGlobal), a centre supported by the "la Caixa" Foundation, and the Barcelona Supercomputing Center - Centro Nacional de Supercomputación (BSC-CNS), has consistently estimated daily ambient concentrations of PM2.5, PM10, NO2 and O3 across a large ensemble of European regions between 2003 and 2019 based on machine learning techniques. The aim was to assess the occurrence of days exceeding the 2021 guidelines of the World Health Organization (WHO) for one or multiple pollutants, referred to as “unclean air days”.
The ...
Multiple air pollutants linked to asthma symptoms in children
2024-03-13
SPOKANE, Wash. – Exposure to several combinations of toxic atmospheric pollutants may be triggering asthma symptoms among children, a recent analysis suggests.
The study, published in the journal Science of the Total Environment, showed that 25 different combinations of air pollutants were associated with asthma symptoms among 269 elementary school children diagnosed with asthma in Spokane, Washington. In line with previous research, the Washington State University-led study revealed a socioeconomic disparity—with one group of children from a lower-income neighborhood exposed to more toxic combinations, a total of 13 of the 25 ...
New computational strategy boosts the ability of drug designers to target proteins inside the membrane
2024-03-13
LA JOLLA, CA—Hitting targets embedded within the cell membrane has long been difficult for drug developers due to the membrane’s challenging biochemical properties. Now, Scripps Research chemists have demonstrated new custom-designed proteins that can efficiently reach these “intramembrane” targets.
In their study, published March 13, 2024, in Nature Chemical Biology, the researchers used a unique computer-based approach to design novel proteins targeting the membrane-spanning region of the erythropoietin (EPO) receptor, which controls red blood cell production and can go awry in cancers. In addition ...
Genetic condition haemochromatosis linked to higher levels of disease in older people
2024-03-13
A largescale new study has found that some people whose genetics are linked to the common iron overload condition haemochromatosis have substantially greater levels of liver, musculoskeletal and brain disease than previously reported, especially at older ages.
Haemochromatosis causes a build-up of iron in the body which can cause harm to joints and organs – although the extent of this harm is unclear, especially in older ages. The new research, led by a team at the University of Exeter and supported by the National Institute for Health and Care ...
Advancing tissue engineering with shape memory hydrogels
2024-03-13
One of the primary goals in the field of tissue engineering and regenerative medicine is the development of artificial scaffolds that can serve as substitutes for damaged tissue. These materials must ideally resemble natural tissue and must have the ability to support cell adhesion, proliferation, and differentiation. When considering scaffold materials, researchers account for the scaffold’s properties, such as its surface roughness, its water content (hydration state), and its flexibility or stiffness (elastic modulus), since these properties are known to affect cell ...
Developing a stem cell therapy to prevent amputations from critical limb ischemia
2024-03-13
Critical limb ischemia is a condition in which the main blood vessels supplying blood to the legs are blocked, causing blood flow to gradually decrease as atherosclerosis progresses in the peripheral arteries. It is a severe form of peripheral artery disease that causes progressive closure of arteries in the lower extremity, leading to the necrosis of the leg tissue and eventual amputation. Current treatments include angioplasty procedures such as stent implantation and anti-thrombotic drugs, but there is a risk of blood vessel damage and recurrence of blood clots, which is why there is a strong interest ...