Showing posts with label Yuri Feldman. Show all posts
Showing posts with label Yuri Feldman. Show all posts

Monday, June 3, 2019

Abstract-The Modeling of the Absorbance of Sub-THz Radiation by Human Skin


Noa Betzalel, Ben Ishai , Yuri Feldman,

https://ieeexplore.ieee.org/document/8016593

In the near future, applications will come online that require data transmission in ultrahigh rates of 100 Gbit per second and beyond. In fact, the planning for new industry regulations for the exploitation of the sub-THz band are well advanced under the auspices of IEEE 802.15 Terahertz Interest Group. One aspect of this endeavor is to gauge the possible impact on human health by the expected explosion in commercial use of this band. It is, therefore, imperative to estimate the respective specific absorption rates of human tissues. In the interaction of microwave radiation and human beings, the skin is traditionally considered as just an absorbing sponge stratum filled with water. This approach is justified when the impinging wavelength is greater than the dimensions of the skin layer. However, in the sub-THz band this condition is violated. In 2008, we demonstrated that the coiled portion of the sweat duct in upper skin layer could be regarded as a helical antenna in the sub-THz band. The full ramifications of what these findings represent in the human condition are still very unclear, but it is obvious that the absorption of electromagnetic energy is governed by the topology for the skin and its organelles, especially the sweat duct.

Saturday, June 1, 2019

Abstract-The human skin as a sub-THz receiver - Does 5G pose a danger to it or not?

Noa Betzalel, Ben Ishai , Yuri Feldman,

https://www.ncbi.nlm.nih.gov/pubmed/29459303

In the interaction of microwave radiation and human beings, the skin is traditionally considered as just an absorbing sponge stratum filled with water. In previous works, we showed that this view is flawed when we demonstrated that the coiled portion of the sweat duct in upper skin layer is regarded as a helical antenna in the sub-THz band. Experimentally we showed that the reflectance of the human skin in the sub-THz region depends on the intensity of perspiration, i.e. sweat duct's conductivity, and correlates with levels of human stress (physical, mental and emotional). Later on, we detected circular dichroism in the reflectance from the skin, a signature of the axial mode of a helical antenna. The full ramifications of what these findings represent in the human condition are still unclear. We also revealed correlation of electrocardiography (ECG) parameters to the sub-THz reflection coefficient of human skin. In a recent work, we developed a unique simulation tool of human skin, taking into account the skin multi-layer structure together with the helical segment of the sweat duct embedded in it. The presence of the sweat duct led to a high specific absorption rate (SAR) of the skin in extremely high frequency band. In this paper, we summarize the physical evidence for this phenomenon and consider its implication for the future exploitation of the electromagnetic spectrum by wireless communication. Starting from July 2016 the US Federal Communications Commission (FCC) has adopted new rules for wireless broadband operations above 24 GHz (5 G). This trend of exploitation is predicted to expand to higher frequencies in the sub-THz region. One must consider the implications of human immersion in the electromagnetic noise, caused by devices working at the very same frequencies as those, to which the sweat duct (as a helical antenna) is most attuned. We are raising a warning flag against the unrestricted use of sub-THz technologies for communication, before the possible consequences for public health are explored.

Friday, June 15, 2018

Abstract-The human skin as a sub-THz receiver – Does 5G pose a danger to it or not?


Noa Betzalel, Paul Ben Ishai, Yuri Feldman,

https://www.sciencedirect.com/science/article/pii/S0013935118300331

In the interaction of microwave radiation and human beings, the skin is traditionally considered as just an absorbing sponge stratum filled with water. In previous works, we showed that this view is flawed when we demonstrated that the coiled portion of the sweat duct in upper skin layer is regarded as a helical antenna in the sub-THz band. Experimentally we showed that the reflectance of the human skin in the sub-THz region depends on the intensity of perspiration, i.e. sweat duct's conductivity, and correlates with levels of human stress (physical, mental and emotional). Later on, we detected circular dichroism in the reflectance from the skin, a signature of the axial mode of a helical antenna. The full ramifications of what these findings represent in the human condition are still unclear. We also revealed correlation of electrocardiography (ECG) parameters to the sub-THz reflection coefficient of human skin. In a recent work, we developed a unique simulation tool of human skin, taking into account the skin multi-layer structure together with the helical segment of the sweat duct embedded in it. The presence of the sweat duct led to a high specific absorption rate (SAR) of the skin in extremely high frequency band. In this paper, we summarize the physical evidence for this phenomenon and consider its implication for the future exploitation of the electromagnetic spectrum by wireless communication. Starting from July 2016 the US Federal Communications Commission (FCC) has adopted new rules for wireless broadband operations above 24 GHz (5 G). This trend of exploitation is predicted to expand to higher frequencies in the sub-THz region. One must consider the implications of human immersion in the electromagnetic noise, caused by devices working at the very same frequencies as those, to which the sweat duct (as a helical antenna) is most attuned. We are raising a warning flag against the unrestricted use of sub-THz technologies for communication, before the possible consequences for public health are explore

Tuesday, August 29, 2017

Abstract-The Modeling of the Absorbance of Sub-THz Radiation by Human Skin



 Noa Betzaleli,  Yuri Feldman,  Paul Ben Ishai,

http://ieeexplore.ieee.org/document/8016593/

In the near future, applications will come online that require data transmission in ultrahigh rates of 100 Gbit per second and beyond. In fact, the planning for new industry regulations for the exploitation of the sub-THz band are well advanced under the auspices of IEEE 802.15 Terahertz Interest Group. One aspect of this endeavor is to gauge the possible impact on human health by the expected explosion in commercial use of this band. It is, therefore, imperative to estimate the respective specific absorption rates of human tissues. In the interaction of microwave radiation and human beings, the skin is traditionally considered as just an absorbing sponge stratum filled with water. This approach is justified when the impinging wavelength is greater than the dimensions of the skin layer. However, in the sub-THz band this condition is violated. In 2008, we demonstrated that the coiled portion of the sweat duct in upper skin layer could be regarded as a helical antenna in the sub-THz band. The full ramifications of what these findings represent in the human condition are still very unclear, but it is obvious that the absorption of electromagnetic energy is governed by the topology for the skin and its organelles, especially the sweat duct.

Monday, May 2, 2016

Terahertz Radiation Shows Great Promise for Medical Advancements



Matthew Weigand

http://www.businesskorea.co.kr/english/news/sciencetech/14571-terahertz-paradigm-terahertz-radiation-shows-great-promise-medical
The 7th International THz-Bio Workshop held at the Koreana Hotel in downtown Seoul on April 6-8 drew a diverse international crowd to speak once again about the beneficial biological effects of one specific kind of radiation. The workshop included speakers from all over the world presenting the latest advancements in the field, vigorous debate about the merits and drawbacks of extremely technical details, and questions about where to take the field next. Some attendees were pure academics, while others were looking at industrial applications. A few had already started companies based on their plans.
The event was chiefly organized by Park Gun-sik, a physics professor at Seoul National University and the director of the Center for THz-Bio Application Systems there, with help from an interdisciplinary and international organizing committee. When asked about the organization’s history, Professor Park said, “Korea initiated the THz-Bio Workshop in the beginning,” and SNU has indeed hosted all seven of the workshops.
The workshop included speakers from far-off places like the U.S., Germany, France, Israel, and Italy, and also some locations closer to Seoul like Russia, Hong Kong, Japan and KAIST, Korea’s top research university. They presented papers about such specific details as the creation of new types of endoscopes using terahertz radiation, but also considered the big-picture ideas of where to focus the field of research in the future. Esoteric considerations of the measurement of intramolecular protein vibrations were discussed alongside more mundane topics of how things are progressing in general five years into a 10-year research program on the topic in Japan.

Terahertz Nuts and Bolts

The entire workshop is based on one specific range of radiation frequencies and its effect on proteins, the building blocks of all life. The radiation is called terahertz radiation. The most popular and well-known type of radiation is, of course, visible light. Our eyes use it every day. Slightly lower on the electromagnetic spectrum with a little less energy and slightly longer wavelengths is infrared radiation, which is most famously used for “night vision” or “heat vision.” Right after infrared is terahertz radiation, which is again slightly lower energy and has wavelengths that range from 0.1 mm down to 1 mm. After terahertz radiation, where the wavelengths increase to 1 cm or longer, is microwave, which is also a very popular type of radiation. So in between night vision and warming up leftover food lies an untapped and precious radiation resource.
The property that makes terahertz radiation precious is the fact that it seems to uniquely react with proteins, which make up everything from bacteria to people. And, not only that, but each different protein seems to react to the terahertz radiation slightly differently. This means that different types of proteins can be identified by their reaction to this radiation, much like x-rays identify the different densities of the different parts of our body, but in potentially much greater detail. Also, some researchers say that it’s possible that proteins can actually be manipulated using terahertz radiation, and these researchers are very excited about the possibilities.

Terahertz Possibilities

One of them is Dr. Ogan Gurel, former director at the Samsung Advanced Institute of Technology and current CEO of NovumWaves, a terahertz technology-based venture company. Dr. Gurel received his medical degree from the Columbia University College of Physicians and Surgeons and did undergraduate research at Harvard with Professor Martin Karplus, a pioneer in protein dynamics and a 2013 Nobel Laureate in Chemistry. He considers the potential biomedical applications of terahertz medicine to be nothing less than a third revolution in medical care. “For thousands of years, one had the medicine side, using drugs, acting on, say, proteins, and the surgery side, whereby hands, supplemented by devices, are used,” Dr. Gurel said in an interview with Business Korea. “The biomedical application of terahertz would be implemented as a device, but this device would be interacting, like drugs do, with molecules, specifically proteins.” So it would not precisely be surgery, and not precisely medicine; he envisions a doctor being able to physically manipulate the body of a patient on the protein level to fix problems.
Currently, drugs are the only way a doctor has to alter proteins, either by inhibiting or activating them. That and surgery are the two possible solutions to any medical problem. But many modern diseases have their roots in protein problems -- from diabetes, to Alzheimer’s disease, to even cancer -- and medicines aren’t always enough to treat them.

Terahertz Challenges

Yuri Feldman, a professor of applied physics at the Hebrew University of Jerusalem, was one of the attendees of the workshop. Business Korea asked him about the challenges that need to be overcome in the area of THz-Bio research. “While the promise of instant diagnostics by molecular signatures is still relevant, the technology of today is inadequate to the task,” he replied. There are power, size and sensitivity requirements that still have not yet been met, although he did admit that there is progress. He also said water in the body was a limiting factor. “Biological applications necessarily happen in damp environments - the body could be described crudely as a sponge soaked in water - and so penetration depths in tissue are limited to a few millimeters at best.” But even then, he said some methods were already being discovered to get around such limitations, such as the possibility of using sweat ducts in the skin as antennas to propagate terahertz radiation further into the body.

Terahertz Progress

“I believe that we had progress in THz-Bio research over the last 7 years,” Professor Park responded when asked about the evolution of the workshop. “Forming an interdisciplinary network is very crucial to this project. We have groups in nanotech, photonics, signal processing, physics, chemistry, dermatology, medical imaging and RF engineers.” He felt that the most significant progress this year has been in biomedical imaging of cells and tissues. “Also the terahertz effect on the biomedical systems and THz-bio interaction, especially with water, has shown progress,” he added.
Dr. Gurel agrees, and he has chosen this year to create his own biomedical startup based on the potential of terahertz-based technology. Business Korea asked him why he decided to take that particular plunge this year. “When launching a company,” he replied, “there are two factors to take into account -- internal factors and external factors. By internal factors, I would say that everything has come together with a absolute world-class team as well as a more mature state of our ideas that makes the time right to start now.” He also pointed out external factors such as the doubling of the number of papers published on the topic every year for the past four years, the 10-fold increase in terahertz-related patent applications, and the emergence of many new companies in the market.
Business Korea asked him what he thought was the greatest strength of his new company, NovumWaves. Dr. Gurel replied, “I would say we have two major strengths: one is our vision to apply terahertz technology into biomedical applications. Other companies have done that, but almost as a ‘side’ effort, rather than a serious, dedicated initiative. Healthcare is complex, involving many different capabilities, not just technology, and a diverse, interconnected ecosystem. This is where our other major strength, our extensive network, is also critical to success. We have relationships with many of the top researchers in the field, many healthcare companies, large and small, research and medical institutions, and so forth. And our network is global.”
New technologies always have a risk associated with them, but with the steady advancement of scientific theory in the THz-Bio field, Korea has a good chance of becoming the epicenter of a whole new way of doing medicine, the terahertz way.