Simulation of the non-thermal effects of strong field terahertz pulses on tumor cells

2021 ◽  
Author(s):  
Zhenzhen Ge ◽  
Jun Zhou ◽  
Shuting Wu ◽  
Xin Rao ◽  
Jiajia Qian ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Thermal Effects ◽  
Strong Field ◽  
Terahertz Pulses

scholarly journals Terahertz quantum plasmonics at nanoscales and angstrom scales

Nanophotonics ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 435-451 ◽  
Author(s):  
Taehee Kang ◽  
Young-Mi Bahk ◽  
Dai-Sik Kim
Keyword(s):  
Electron Tunneling ◽  
Strong Field ◽  
Field Enhancement ◽  
Dipole Antenna ◽  
Strong Light ◽  
Metallic Structures ◽  
Terahertz Pulses ◽  
Matter Interaction ◽  
Light Matter Interaction ◽  
Quantum Phenomena

AbstractThrough the manipulation of metallic structures, light–matter interaction can enter into the realm of quantum mechanics. For example, intense terahertz pulses illuminating a metallic nanotip can promote terahertz field–driven electron tunneling to generate enormous electron emission currents in a subpicosecond time scale. By decreasing the dimension of the metallic structures down to the nanoscale and angstrom scale, one can obtain a strong field enhancement of the incoming terahertz field to achieve atomic field strength of the order of V/nm, driving electrons in the metal into tunneling regime by overcoming the potential barrier. Therefore, designing and optimizing the metal structure for high field enhancement are an essential step for studying the quantum phenomena with terahertz light. In this review, we present several types of metallic structures that can enhance the coupling of incoming terahertz pulses with the metals, leading to a strong modification of the potential barriers by the terahertz electric fields. Extreme nonlinear responses are expected, providing opportunities for the terahertz light for the strong light–matter interaction. Starting from a brief review about the terahertz field enhancement on the metallic structures, a few examples including metallic tips, dipole antenna, and metal nanogaps are introduced for boosting the quantum phenomena. The emerging techniques to control the electron tunneling driven by the terahertz pulse have a direct impact on the ultrafast science and on the realization of next-generation quantum devices.

scholarly journals Non-Thermal Intervention of Lung Tumor by Core-Shell Magnetic Nanoparticles in a Magnetic Field

2021 ◽  
Vol 11 (5) ◽  
pp. 2003
Author(s):  
Naming Zhang ◽  
Ziang Wang ◽  
Shuya Ning ◽  
Shuhong Wang ◽  
Song Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Nanoparticles ◽  
Tumor Cells ◽  
Thermal Effects ◽  
Magnetic Stimulation ◽  
Magnetic Force ◽  
Lung Tumor ◽  
Wound Healing Assay ◽  
Inhibitory Effects ◽  
Normal Cells

K-Ras mutations result in normal cells dividing uncontrollably and becoming cancerous. The prognosis is currently poor for patients due to the lack of drugs that can effectively target these mutations. In this study, magnetic nanoparticles (MNPs) were prepared, characterized, and cooperated with a magnetic field to intervene in the growth of lung tumor cells. The rise in temperature of a stimulation coil was studied by numerical calculation. The non-thermal effects of MNPs under a magnetic force were analyzed. The cell experiments showed that the growth of A549 tumor cells slowed down. The result of a wound-healing assay also indicated that the migration of tumor cells was suppressed. Compared with magnetic stimulation without MNPs, MNPs enhanced the inhibitory effects of a magnetic field. This study suggests a new way to treat K-Ras driven lung tumors using non-thermal effects of MNPs without the side effects caused by thermal effects.

scholarly journals Селективное возбуждение и создание инверсной населенности в квантовых системах с помощью униполярных аттосекундных и терагерцовых импульсов

2020 ◽  
Vol 128 (12) ◽  
pp. 1905
Author(s):  
Р.М. Архипов ◽  
М.В. Архипов ◽  
А.В. Пахомов ◽  
М.О. Жукова ◽  
А.Н. Цыпкин ◽  
...  
Keyword(s):  
Strong Field ◽  
Energy Levels ◽  
Weak Field ◽  
Quantum Systems ◽  
Spatial Profile ◽  
Terahertz Pulses ◽  
Selective Population ◽  
Dynamics Of Population ◽  
The Impact ◽  
Level Medium

The possibility of selective population of the energy levels of quantum systems was studied using a single unipolar subcycle pulse and a pair of pulses. Selective population of quantum levels is clearly illustrated based on the numerical solution of the system of equations for the density matrix of a three-level medium interacting with a pair of subcycle attosecond and terahertz pulses. The possibility of creating an population inversion in a three-level medium is shown using a pair of such pulses. The dynamics of population density gratings in a three-level medium is studied at the impact on the system of a pair of large-amplitude Gaussian pulses. If in a weak field the shape of the gratings is harmonic, according to analytical calculations performed according to perturbation theory, then in in the case of a strong field, the spatial profile of the gratings can differ from the sinusoidal one and has complex spike structure.

High-Energy Strong-Field Terahertz Pulses Based on Tilted-Pulse-Front Technique

2019 ◽  
Vol 46 (6) ◽  
pp. 0614008
Author(s):  
吴晓君 Xiaojun Wu ◽  
郭丰玮 Fengwei Guo ◽  
马景龙 Jinglong Ma ◽  
欧阳琛 Chen Ouyang ◽  
王天泽 Tianze Wang ◽  
...  
Keyword(s):  
Strong Field ◽  
High Energy ◽  
Pulse Front ◽  
Terahertz Pulses

scholarly journals Generation of strong-field spectrally tunable terahertz pulses

2020 ◽  
Vol 28 (23) ◽  
pp. 33921
Author(s):  
A. V. Ovchinnikov ◽  
O. V. Chefonov ◽  
M. B. Agranat ◽  
V. E. Fortov ◽  
M. Jazbinsek ◽  
...  
Keyword(s):  
Strong Field ◽  
Terahertz Pulses

Membranous alterations in the cytoplasm and nucleus in a primitive neuroectodermal tumor of the brain

1978 ◽  
Vol 36 (2) ◽  
pp. 628-629
Author(s):  
C. N. Sun ◽  
C. Araoz ◽  
H. J. White
Keyword(s):  
Nuclear Envelope ◽  
Tumor Cells ◽  
Osmium Tetroxide ◽  
Primitive Neuroectodermal Tumor ◽  
Uranyl Acetate ◽  
Neuroectodermal Tumor ◽  
Annulate Lamellae ◽  
Lead Citrate ◽  
Thin Sections ◽  
The Brain

The ultrastructure of a cerebral primitive neuroectodermal tumor has been reported previously. In the present case, we will present some unusual previously unreported membranous structures and alterations in the cytoplasm and nucleus of the tumor cells.Specimens were cut into small pieces about 1 mm3 and immediately fixed in 4% glutaraldehyde in phosphate buffer for two hours, then post-fixed in 1% buffered osmium tetroxide for one hour. After dehydration, tissues were embedded in Epon 812. Thin sections were stained with uranyl acetate and lead citrate.In the cytoplasm of the tumor cells, we found paired cisternae (Fig. 1) and annulate lamellae (Fig. 2) noting that the annulate lamellae were sometimes associated with the outer nuclear envelope (Fig. 3). These membranous structures have been reported in other tumor cells. In our case, mitochondrial to nuclear envelope fusions were often noted (Fig. 4). Although this phenomenon was reported in an oncocytoma, their frequency in the present study is quite striking.

Thermal Considerations in Lens Regulator Systems

1970 ◽  
Vol 28 ◽  
pp. 358-359
Author(s):  
K.C. Newton
Keyword(s):  
Electron Microscope ◽  
Thermal Effects ◽  
Environmental Control ◽  
Reference Networks ◽  
Better Than

Thermal effects in lens regulator systems have become a major problem with the extension of electron microscope resolution capabilities below 5 Angstrom units. Larger columns with immersion lenses and increased accelerating potentials have made solutions more difficult by increasing the power being handled. Environmental control, component choice, and wiring design provide answers, however. Figure 1 indicates with broken lines where thermal problems develop in regulator systemsExtensive environmental control is required in the sampling and reference networks. In each case, stability better than I ppm/min. is required. Components with thermal coefficients satisfactory for these applications without environmental control are either not available or priced prohibitively.

Ulcerogenic Tumors of the Pancreas

1968 ◽  
Vol 26 ◽  
pp. 186-187
Author(s):  
J. C. Garancis ◽  
J. F. Kuzma ◽  
S. D. Wilson ◽  
E. H. Ellison
Keyword(s):  
Endoplasmic Reticulum ◽  
Tumor Cells ◽  
Islet Cell ◽  
Disease Process ◽  
Central Core ◽  
Islet Cell Tumors ◽  
Opaque Zone ◽  
Granular Form ◽  
Zollinger Ellison Syndrome

It has been proposed that a gastrin-like hormone elaborated by non-beta islet tumors of the pancreas may be responsible for a fulminating ulcer diathesis. Subsequently, a potent gastric secretagogue was isolated from ulcerogenic tumors of the pancreas. This disease process is known now as “Zollinger-Ellison syndrome”.In our studies of two cases of Zollinger-Ellison syndrome, pancreatic lesions were identified as alpha islet cell tumors (Fig. 1). Tumor cells were fairly uniform. The sizes of the alpha granules were not significantly different, but their number and distribution varied greatly from one cell to another. Each granule consisted of a round, highly dense central core, separated from the limiting membrane by an opaque zone. The granular form of the endoplasmic reticulum was particularly prominent. Numerous mitochondria, round or elongated, were dispersed throughout the cytoplasm. Individual or clusters of lysosomes were observed in the majority of cells.

High resolution STEM imaging study on high Tc superconductor YBa2CuaO7-x

1988 ◽  
Vol 46 ◽  
pp. 882-883
Author(s):  
H.-J. Ou ◽  
J. M. Cowley
Keyword(s):  
Crystal Structure ◽  
High Resolution ◽  
Grain Boundary ◽  
Strong Field ◽  
Imaging Study ◽  
Structure Defects ◽  
High Tc ◽  
High Tc Superconductor ◽  
Diffraction Patterns ◽  
Lattice Planes

Using the dedicate VG-HB5 STEM microscope, the crystal structure of high Tc superconductor of YBa2Cu3O7-x has been studied via high resolution STEM (HRSTEM) imaging and nanobeam (∽3A) diffraction patterns. Figure 1(a) and 2(a) illustrate the HRSTEM image taken at 10' times magnification along [001] direction and [100] direction, respectively. In figure 1(a), a grain boundary with strong field contrast is seen between two crystal regions A and B. The grain boundary appears to be parallel to a (110) plane, although it is not possible to determine [100] and [001] axes as it is in other regions which contain twin planes [3]. Following the horizontal lattice lines, from left to right across the grain boundary, a lattice bending of ∽4° is noticed. Three extra lattice planes, indicated by arrows, were found to terminate at the grain boundary and form dislocations. It is believed that due to different chemical composition, such structure defects occur during crystal growth. No bending is observed along the vertical lattice lines.

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