The findings help to better understand movement of nano-sized objects in fluid environments that can be characterized by a low Reynolds number, which often occurs in biological systems. The unconventional results are consistent with Newton’s Second Law of Motion, a well-established law of physics, and imply that mass should be included in the dynamic model of these nano-systems. The most widely accepted models omit mass at that scale.
Alan Bowling, an assistant professor of mechanical and aerospace engineering, collaborated with Samarendra Mohanty, an assistant physics professor, and doctoral students Mahdi Haghshenas-Jaryani, Bryan Black and Sarvenaz Ghaffari, as well as graduate student James Drake to make the discovery.
A key advantage of the new model is that it can be used to build computer simulations of nano-sized objects that have drastically reduced run times as compared to a conventional model based on Newton’s second law. These conventional models have run times of days, weeks, months and years while the new model requires only seconds or minutes to run.
In the past, researchers attempted to address the long run time by omitting the mass terms in the model. This resulted in faster run times but, paradoxically, violated Newton’s second law upon which the conventional model was based. The remedy for this paradox was to argue that mass was unimportant at the nano-scale.
However, the new model retains mass, and predicts unexpected motion of nano-sized objects in a fluid that has been experimentally observed. The new model also runs much faster than both the conventional and massless models.
It is expected that this new model will significantly accelerate research involving small-scale phenomena.
Research areas that Bowling and collaborators at UT Arlington are currently investigating include cell migration, protein function, bionic medical devices and nanoparticle suspensions for storing thermal energy. However, the applications for the computer simulation in medicine, biology, and other fields are endless.
The research is detailed in the paper “Dynamics of Microscopic Objects in Optical Tweezers: Experimental Determination of Underdamped Regime and Numerical Simulation using Multiscale Analysis” and published online by the Journal of Non-Linear Dynamics. The paper is scheduled for publication in the journal’s print version later this year.
Khosrow Behbehani, dean of the College of Engineering, said the team’s findings may alter ways of thinking throughout the engineering and scientific worlds.
“The paper is only the beginning for this research,” Behbehani said. “I anticipate a high level of interest in the findings. It could transform the way we conduct research in nano-engineering by providing researchers with the ability to study such physical phenomena at such small scale through the model.”
The team used optical tweezers previously developed by Mohanty to measure oscillations that occur at the nano scale, thus proving that mass and acceleration must be considered at that level as well.
“We proved it in the lab,” Bowling said. “Publication in an accepted journal is the next step in gaining mass acceptance of the idea, which flies in the face of what most people believe now.”
The discovery resulted from a 2012 National Science Foundation grant project in which the UT Arlington team investigated a new model for how motor proteins behave in the body. The NSF award was funded through the Early Concept Grants for Exploratory Research, or EAGER program. The grants support exploratory work in its early stages on untested, but potentially transformative, research ideas or approaches.
The University of Texas at Arlington is a comprehensive research institution of more than 33,300 students and 2,300 faculty members in the epicenter of North Texas. It is the second largest institution in the University of Texas System. Research expenditures reached almost $78 million last year. Visit www.uta.edu for more information.
Herb Booth | EurekAlert!
Writing and deleting magnets with lasers
19.04.2018 | Helmholtz-Zentrum Dresden-Rossendorf
Ultrafast electron oscillation and dephasing monitored by attosecond light source
19.04.2018 | Yokohama National University
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.
Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
19.04.2018 | Materials Sciences
19.04.2018 | Physics and Astronomy
19.04.2018 | Physics and Astronomy