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Electromagnetic Radiation

Alberto Foletti, Larissa Brizhik
Biological organisms are complex open dissipative systems whose dynamical stability is sustained due to the exchange of matter, energy and information. Dynamical stability occurs through a number of mechanisms that sustain efficient adaptive dynamics. Such properties of living matter can be the consequence of a self-consistent state of matter and electromagnetic field (EMF). Based on the soliton model of charge transport in redox processes, we describe a possible mechanism of the origin of endogenous EMF and coherence...
September 22, 2017: Electromagnetic Biology and Medicine
Th I Götz, G Lahmer, V Strnad, Ch Bert, B Hensel, A M Tomé, E W Lang
During High Dose Rate Brachytherapy (HDR-BT) the spatial position of the radiation source inside catheters implanted into a female breast is determined via electromagnetic tracking (EMT). Dwell positions and dwell times of the radiation source are established, relative to the patient's anatomy, from an initial X-ray-CT-image. During the irradiation treatment, catheter displacements can occur due to patient movements. The current study develops an automatic analysis tool of EMT data sets recorded with a solenoid sensor to assure concordance of the source movement with the treatment plan...
2017: PloS One
Haotian Wu, Shuo Liu, Xiang Wan, Lei Zhang, Dan Wang, Lianlin Li, Tie Jun Cui
Metamaterials are artificial structures composed of subwavelength unit cells to control electromagnetic (EM) waves. The spatial coding representation of metamaterial has the ability to describe the material in a digital way. The spatial coding metamaterials are typically constructed by unit cells that have similar shapes with fixed functionality. Here, the concept of frequency coding metamaterial is proposed, which achieves different controls of EM energy radiations with a fixed spatial coding pattern when the frequency changes...
September 2017: Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
Werner Jaross
The molecular vibration patterns of structure-forming macromolecules in the living cell create very specific electromagnetic frequency patterns which might be used for information on spatial position in the three-dimensional structure as well as the chemical characteristics. Chemical change of a molecule results in a change of the vibration pattern and thus in a change of the emitted electromagnetic frequency pattern. These patterns have to be received by proteins responsible for the necessary interactions and functions...
January 1, 2018: Frontiers in Bioscience (Landmark Edition)
Hugo Jimenez, Carl Blackman, Glenn Lesser, Waldemar Debinski, Michael Chan, Sambad Sharma, Kounosuke Watabe, Hui-Wen Lo, Alexandra Thomas, Dwayne Godwin, William Blackstock, Albert Mudry, James Posey, Rodney O'Connor, Ivan Brezovich, Keith Bonin, Daniel Kim-Shapiro, Alexandre Barbault, Boris Pasche
Cancer treatment and treatment options are quite limited in circumstances such as when the tumor is inoperable, in brain cancers when the drugs cannot penetrate the blood-brain-barrier, or when there is no tumor-specific target for generation of effective therapeutic antibodies. Despite the fact that electromagnetic fields (EMF) in medicine have been used for therapeutic or diagnostic purposes, the use of non-ionizing EMF for cancer treatment is a new emerging concept. Here we summarize the history of EMF from the 1890's to the novel and new innovative methods that target and treat cancer by non-ionizing radiation...
January 1, 2018: Frontiers in Bioscience (Landmark Edition)
Pable Ulloa, Monica Pacheco, Andrea Latge
Here we present a theoretical study of the optical properties of graphene nanocones tuned by external electric and magnetic fields. We investigate the effects of the size and topology of the carbon nanostructures on the density of states and on the electro- and magneto-absorption of linearly polarized electromagnetic radiation in different nanocone geometries. We find that the electric field induces changes in the electric charge distribution mainly at the cone edges. In the infrared range the absorption coefficient shows a peculiar dependence on the electric field (magnitude and direction) and on the photon polarization for all investigated structures...
September 20, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
JingYa Xie, Xi Zhu, XiaoFei Zang, QingQing Cheng, YangYang Ye, YiMing Zhu
A high extinction ratio (ER) electromagnetically induced transparency (EIT) analogue based on single-layer metamaterial is designed and experimentally demonstrated in this paper. This design involves four mirror-like symmetrically coupled split ring resonators (SRRs) that exhibit a bright-dark-dark-bright mode configuration. The EIT-like effect is realized by coupling between the bright resonators and dark resonators. The high ER feature is achieved from the suppression of radiative losses, due to opposite directions of electric and magnetic dipoles of two dark modes in the unit cell...
September 12, 2017: Scientific Reports
Wendao Xu, Lijuan Xie, Yibin Ying
Terahertz (THz) technology has attracted great worldwide interest and novel high-intensity THz sources and plasmonics are two of the most active fields of recent research. Being situated between infrared light and microwave radiation, the absorption of THz rays in molecular and biomolecular systems is dominated by the excitation of intramolecular and intermolecular vibrations. This indicates that THz technology is an effective tool for sensing applications. However, the low sensitivity of free-space THz detection limits the sensing applications, which gives a great opportunity to metamaterials...
September 12, 2017: Nanoscale
Mary Hydrina D'Silva, Rijied Thompson Swer, J Anbalagan, Bhargavan Rajesh
INTRODUCTION: The increasing scientific evidence of various health hazards on exposure of Radiofrequency Radiation (RFR) emitted from both the cell phones and base stations have caused significant media attention and public discussion in recent years. The mechanism of interaction of RF fields with developing tissues of children and fetuses may be different from that of adults due to their smaller physical size and variation in tissue electromagnetic properties. The present study may provide an insight into the basic mechanisms by which RF fields interact with developing tissues in an embryo...
July 2017: Journal of Clinical and Diagnostic Research: JCDR
Zhenyun Qian, Sungho Kang, Vageeswar Rajaram, Cristian Cassella, Nicol E McGruer, Matteo Rinaldi
State-of-the-art sensors use active electronics to detect and discriminate light, sound, vibration and other signals. They consume power constantly, even when there is no relevant data to be detected, which limits their lifetime and results in high costs of deployment and maintenance for unattended sensor networks. Here we propose a device concept that fundamentally breaks this paradigm-the sensors remain dormant with near-zero power consumption until awakened by a specific physical signature associated with an event of interest...
September 11, 2017: Nature Nanotechnology
Kun Zhang, Fan Wu, Aming Xie, Mengxiao Sun, Wei Dong
The design of novel hybrid nanostructures has been seemed as an effective route to tune the properties of materials. Herein, we provide an in situ growth strategy to efficiently construct kebab-like hybrids, which are composed of one-dimensional SiC nanowires stringing polyhedral MOFs. Through a heat-treatment process regardless of under air or argon, these hybrids generate excellent electromagnetic absorption (EMA) ability. We comprehensively explored the growth and calcination process of these hybrids as well as their EMA enhanced mechanism...
September 7, 2017: ACS Applied Materials & Interfaces
D A Walsh, D S Lake, E W Snedden, M J Cliffe, D M Graham, S P Jamison
The sub-luminal phase velocity of electromagnetic waves in free space is generally unobtainable, being closely linked to forbidden faster than light group velocities. The requirement of sub-luminal phase-velocity in laser-driven particle acceleration schemes imposes a limit on the total acceleration achievable in free space, and necessitates the use of dispersive structures or waveguides for extending the field-particle interaction. We demonstrate a travelling source approach that overcomes the sub-luminal propagation limits...
September 4, 2017: Nature Communications
Sitansu Sekhar Nanda, Min Jik Kim, Kwangmeyung Kim, Georgia C Papaefthymiou, Subramanian Tamil Selvan, Dong Kee Yi
Quantum confinement in inorganic semiconductor nanocrystals produces brightly luminescent nanoparticles endowed with unique photo-physical properties, such as tunable optical properties. These have found widespread applications in nanotechnology. The ability to render such nanostructures biocompatible, while maintaining their tunable radiation in the visible range of the electromagnetic spectrum, renders them appropriate for bio-applications. Promising in vitro and in vivo diagnostic applications have been demonstrated, such as fluorescence-based detection of biological interactions, single molecule tracking, multiplexing and immunoassaying...
August 25, 2017: Colloids and Surfaces. B, Biointerfaces
Theresa Ida Götz, Maximilian Ermer, D Salas-Gonzalez, Markus Kellermeier, Vratislav Strnad, Christoph Bert, Bernhard Hensel, Ana Maria Tome, Elmar W Lang
High Dose Rate Brachytherapy (HDR-BT) affords a frequent reassurance of the precise dwell positions of the radiation source. The corresponding dwell position determinations are realized with an electromagnetic tracking system (EMT). Because the treatment extends over several days, repeated dwell position determinations refer to varying coordinate systems centered in the field generator of the EMT system. After surgical implantation of the catheters a computed tomography (CT) X-ray image is taken followed by an immediate dwell position determination by the EMT system...
August 30, 2017: Physics in Medicine and Biology
Rebecca Myatt
Rationale and key points X-ray imaging is a form of electromagnetic radiation that is able to pass through the human body producing an image of the internal structures. X-rays are one of the main investigations for confirming a suspected diagnosis. Developing an understanding of the underlying mechanism and the rationale for requesting an X-ray will increase nurses' understanding of the process and enable improved patient preparation through explanation and reassurance. This article provides an overview of the fundamental principles underlying the process of obtaining an X-ray...
August 30, 2017: Nursing Standard
M H Repacholi
Concern about health risks from exposure to non-ionizing radiation (NIR) commenced in the 1950s after tracking radars were first introduced during the Second World War. Soon after, research on possible biological effects of microwave radiation in the former Soviet Union and the U.S. led to public and worker exposure limits being much lower in Eastern European than in Western countries, mainly because of different protection philosophies. As public concern increased, national authorities began introducing legislation to limit NIR exposures from domestic microwave ovens and workplace devices such as visual display units...
October 2017: Health Physics
F M de Oliveira, A M Carmona, C Ladeira
Electromagnetic fields (EMF) are classified as "possibly carcinogenic" by the International Agency for Research on Cancer (IARC). Some publications have reported associations between EMF exposure and DNA damage, but many other studies contradict such findings. Cytomorphological changes, such as micronuclei (MN), indicative of genomic damage, are biomarkers of genotoxicity. To test whether mobile phone-associated EMF exposure affects the MN frequency in exfoliated buccal cells, we obtained cells smears from the left and right inner cheeks of healthy mobile phone users, aged 18-30 (n=86), who also completed a characterization survey...
October 2017: Mutation Research
Jacob L Poole, Yang Yu, Paul R Ohodnicki
Electromagnetic fields produced by thermal fluctuation can excite the near-field optical states, creating the potential for thermal radiation orders of magnitude greater than what is predicted by Plank's blackbody theory. The typical schemes employed to probe the trapped electromagnetic energy of the near-field are with considerable technical challenges, suffering from scalability and high costs, hindering widespread use. A waveguide-based scheme relying on photon tunneling is presented as an alternate approach, as waveguides inherently provide a large density of channels for photons to tunnel to with the required k-vector matching and probability density overlap...
August 25, 2017: Scientific Reports
Ana Marija Marjanovic Cermak, Ivan Pavicic, Blanka Tariba Lovakovic, Alica Pizent, Ivancica Trosic
In this study possible connection between radiofrequency exposure (RF) and development of oxidative stress was investigated by measuring impairment in cellular oxidation-reduction balance immediately after RF exposure. Fibroblast cells V79 were exposed for 10, 30 and 60 minutes to 1800 MHz RF radiation. Electric field strength was 30 V/m and specific absorption rate (SAR) was calculated to be 1.6 W/kg. Electromagnetic field was generated within Gigahertz Transversal Electromagnetic Mode cell (GTEM) equipped by signal generator, amplifier and modulator...
August 24, 2017: General Physiology and Biophysics
Tianxiang Nan, Hwaider Lin, Yuan Gao, Alexei Matyushov, Guoliang Yu, Huaihao Chen, Neville Sun, Shengjun Wei, Zhiguang Wang, Menghui Li, Xinjun Wang, Amine Belkessam, Rongdi Guo, Brian Chen, James Zhou, Zhenyun Qian, Yu Hui, Matteo Rinaldi, Michael E McConney, Brandon M Howe, Zhongqiang Hu, John G Jones, Gail J Brown, Nian Xiang Sun
State-of-the-art compact antennas rely on electromagnetic wave resonance, which leads to antenna sizes that are comparable to the electromagnetic wavelength. As a result, antennas typically have a size greater than one-tenth of the wavelength, and further miniaturization of antennas has been an open challenge for decades. Here we report on acoustically actuated nanomechanical magnetoelectric (ME) antennas with a suspended ferromagnetic/piezoelectric thin-film heterostructure. These ME antennas receive and transmit electromagnetic waves through the ME effect at their acoustic resonance frequencies...
August 22, 2017: Nature Communications
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