.This content is not available for your level
.To access this content, register your upgrade request if you are eligible
.This content is not available for your level
.To access this content, register your upgrade request if you are eligible
Ultrasound can be focused into deep tissues with millimeter precision to perform noninvasive ablative therapy for diseases such as cancer. In most cases, this ablation uses high-intensity ultrasound to deposit nonselective thermal or mechanical energy at the ultrasound focus, damaging both healthy bystander tissue and cancer cells. Here, we describe an alternative low intensity (I_(SPTA) < 5 W/cm²) pulsed ultrasound approach that leverages the distinct mechanical properties of neoplastic cells to achieve inherent cancer selectivity. We show that ultrasound applied at a frequency of 0.5–0.67 MHz and a pulse duration of >20 ms causes selective disruption of a panel of breast, colon, and leukemia cancer cell models in suspension without significantly damaging healthy immune or red blood cells. Mechanistic experiments reveal that the formation of acoustic standing waves and the emergence of cell-seeded cavitation leads to cytoskeletal disruption, expression of apoptotic markers, and cell death. The inherent selectivity of this low-intensity pulsed ultrasound approach offers a potentially safer and thus more broadly applicable alternative to nonselective high-intensity ultrasound ablation.
Mittelstein, David R et al
Applied Physics Letters, (2020), 116 (1). Art. No. 013701. ISSN 0003-6951.
Cancer research is increasingly focused on discovering strategies to induce cancer cell apoptosis without affecting surrounding normal cells. One potential biocompatible method is mechanical vibration, which has been developed as part of the emerging field of mechanomedicine. Previous studies of mechanical vibration have employed high-frequency vibration, which damages healthy cells. In this study, we examined the effects of brief (1 h) low-frequency (20 Hz) mechanical vibration on glucose consumption and survival (apoptosis, necrosis, HMGB1 release) of the human epidermoid carcinoma cell line A431. We found that apoptosis, but not necrosis, was significantly increased at 48 h after mechanical vibration compared with cells maintained in static culture. In keeping with this, extracellular release of HMGB1, a necrosis marker, was lower in cultures of A431 cells subjected to mechanical vibration compared with control cells. Glucose consumption was increased in the first 24 h after mechanical vibration but returned to control levels before the onset of apoptosis. Although the precise intracellular mechanisms by which low-frequency mechanical vibration triggers apoptosis of A431 cells is unknown, these results suggest a possible role for metabolic pathways. Mechanical vibration may thus represent a novel application of mechanomedicine to cancer therapy.
Skeletal muscle consists of long plurinucleate and contractile structures, able to regenerate and repair tissue damage by their resident stem cells: satellite cells (SCs). Reduced skeletal muscle regeneration and progressive atrophy are typical features of sarcopenia, which has important health care implications for humans. Sarcopenia treatment is usually based on physical exercise and nutritional plans, possibly associated with rehabilitation programs, such as vibratory stimulation. Vibrations stimulate muscles and can increase postural stability, balance, and walking in aged and sarcopenic patients. However, the possible direct effect of vibration on SCs is still unclear. Here,
we show the effects of focused vibrations administered at increasing time intervals on SCs, isolated from young and aged subjects and cultured in vitro. After stimulations, we found in both young and aged subjects a reduced percentage of apoptotic cells, increased cell size and percentage of aligned cells, mitotic events, and activated cells. We also found an increased number of cells only in young samples. Our results highlight for the first time the presence of direct effects of mechanical vibrations on human SCs. These effects seem to be age-dependent, consisting of a proliferative response of cells derived from young subjects vs. a differentiative response of cells from aged subjects.
Silvia Sancilio et al
international journal of molecular sciences
Cancer treatment by magneto-mechanical effect of particles (TMMEP) is a growing field of research. The principle of this technique is to apply a mechanical force on cancer cells in order to destroy them thanks to magnetic particles vibrations. For this purpose, magnetic particles are injected in the tumor or exposed to cancer cells and a low-frequency alternating magnetic field is applied. This therapeutic approach is quite new and a wide range of treatment parameters are explored to date, as described in the literature. This review explains the principle of the technique, summarizes the parameters used by the different groups and reports the main in vitro and in vivo results.
Cécile Naud et al
The Royal Society of Chemistry 2020
The Great Pyramid or Khufu’s Pyramid was built on the Giza Plateau (Egypt) during the IVth dynasty by the pharaoh Khufu (Cheops), who reigned from 2509 to 2483 BC1. Despite being one of the oldest and largest monuments on Earth, there is no consensus about how it was built. To better understand its internal structure, we imaged the pyramid using muons, which are by-products of cosmic rays that are only partially absorbed by stone. The resulting cosmic-ray muon radiography allows us to visualize the known and potentially unknown voids in the pyramid in a non-invasive way. Here we report the discovery of a large void (with a cross section similar to the Grand Gallery and a length of 30 m minimum) above the Grand Gallery, which constitutes the first major inner structure found in the Great Pyramid since the 19th century1.
This void, named ScanPyramids Big Void, was first observed with nuclear emulsion films7,8,9 installed in the Queen’s chamber (Nagoya University), then confirmed with scintillator hodoscopes10,11 set up in the same chamber (KEK) and reconfirmed with gas detectors12 outside of the pyramid (CEA). This large void has therefore been detected with a high confidence by three different muon detection technologies and three independent analyses. These results constitute a breakthrough for the understanding of Khufu’s Pyramid and its internal structure. While there is currently no information about the role of this void, these findings show how modern particle physics can shed new light on the world’s archaeological heritage.
Article in Nature · December 2017
The Pierre Auger Observatory in Argentina has spent almost ten years looking for the source of ultra-high-energy cosmic rays — but to no avail. Now the observatory faces an uncertain future.
The tank looks oddly out of place here on the windy Pampas of western Argentina. Surrounded by yellow grass and spiky thorn bushes, the chest-high plastic cylinder
could be some kind of storage container — were it not for the bird-spattered solar panels and antennas on top.
More tanks can be seen in the distance, illuminated by a crimson Sun dropping behind the far-off Andes. “Some locals think that the tanks influence the weather: they make it rain or snow, or make a dry season,” says Anselmo Francisco Jake, the farmer who owns this stretch of land. “But I know they don’t. I know they catch cosmic rays.”
Jake is right. There are 1,600 of these tanks, spaced over a 3,000-square-kilometre expanse that could fit all of Luxembourg with room
to spare. Together they comprise the Pierre Auger Observatory: a US$53-million experiment to reveal the mysterious origins of ultra-high-energy cosmic rays, the most energetic subatomic particles known to exist.
But for all its size, the array has fallen short. After almost ten years of hunting, it has observed dozens of ultra-high-energy cosmic rays but has not managed to solve the mystery of where they come from. As a detector, “the device worked twice as well as we expected”, says project co-founder James Cronin, a retired astrophysicist at the University of Chicago in Illinois. But the particles seem to be coming from all over the sky, with too little clustering for researchers to pinpoint the sources. “It’s up to nature with experiments like this one,” he says.
Now, the Auger team is putting its hopes on a proposed upgrade that might settle the question by improving Auger’s resolution considerably. Five designs are being evaluated internally by a committee of Auger physicists, who are expected to present their final selection to the array’s many funding agencies in November. The trouble is, there is a sixth option, too. “In the worst-case scenario, and I don’t want to think about it, we may get shut down,” says Auger’s deputy project manager, physicist Ingo Allekotte.
An upgrade would require an investment of roughly $15 million, and some argue that the money would be put to better use elsewhere. “Although it was worth building Auger, it was a gamble that unfortunately didn’t yield much new understanding,” says Eric Adelberger, a physicist at the University of Washington in Seattle. “Cosmic-ray physics has delivered very few surprises and progress is terribly slow. Maybe it is time to move on.”
That would be a blow to science — and to Argentina, say Auger’s supporters. These flagship projects do more than just conduct research, says Pablo Mininni, head of the physics department at the University of Buenos Aires. They also raise awareness of physics and draw young people into the field. “Such a big project deserves some continuity,” he says.
Physicists have known for more than a century that Earth is continually bombarded by charged particles from space — many of which have energies that are astonishing even by particle-physics standards. It is not uncommon for cosmic rays to have hundreds or thousands of times the 7 trillion electron volts (1012 eV) soon to be achieved by the most powerful human-made particle accelerator, the Large Hadron Collider (LHC) near Geneva in Switzerland.
Most of these particles are now thought to be protons and other light nuclei originating far outside the Solar System, probably in cataclysmic stellar explosions known as supernovas. But on very rare occasions, cosmic rays have hit Earth’s atmosphere at energies of 1018 eV or more. The most energetic example on record — the ‘Oh-My-God particle’ detected1 on 15 October 1991 in the skies above Utah — had 3×1020 eV, about 40 million times that of the LHC. And therein lies a mystery: calculations suggest that the expanding shock wave of a supernova detonation cannot accelerate charged particles beyond about 1017 eV. No one knows what physical process
could accelerate particles to higher energies — or even what those particles might be (see Nature 448, 8–9; 2007).
22 | NATURE | VOL 514 | 2 OCTOBER 2014
This book describes adventures in different parts of the world studding the energies – energy of the particular place and energy of people being in this place. It is written by mountaineer, professor and a world renown scientist, who has devoted his life to the study of spiritual worlds from a scientific perspective. Science, Information, and Spirit – this is a recurring slogan of his work for many years, and also is the name for annual international congresses held in Saint-Petersburg every July. This book describes a new revolutionary approach to study of geo-active zones, based on many years of scientific research. Life – is a great adventure in our everyday reality, and you may receive a strong impulse of optimism by reading this book.
Translated from Russian by the author and Artem Raskin
with the help of many friends.
Photos by the author.
Cover picture by Oleg Bazhenov
© 2016 Korotkov Konstanti
Spastic diplegia is a common form of cerebral palsy (CP) and is characterized by spasticity and muscle weakness of both lower limbs resulting in decreased walking ability. The purpose of this study was to evaluate the effect of whole body vibration (WBV) training on muscle strength, spasticity, and motor performance in spastic diplegic cerebral palsy children after 12-weeks treatment.
Thirty spastic diplegic CP children (8–12 years) were randomized to two equal groups, control group and WBV group. The control group received a selected physical therapy treatment program for spastic diplegic CP and the WBV group received the same program in addition to WBV training. Measurements of isometric strength of knee extensors, spasticity, walking speed, walking balance and gross motor function were performed before and after 12 weeks of the treatment program.
Isometric strength of knee extensors, spasticity and the walking speed were significantly improved only in the WBV group (P < 0.05). Growth motor function measure-88 (GMFM-88) (D%) was significantly increased (P < 0.05) in both groups in favor of the WBV group and GMFM-88 (E%) was significantly increased (P < 0.05) only in the WBV group, while walking balance did not change significantly in either group.
The obtained results suggest that 12-weeks’ intervention of whole-body vibration training can increase knee extensors strength and decrease spasticity with beneficial effects on walking speed and motor development in spastic diplegic CP children.
The choice of the operating wavelength of electromagnetic radiation is justified for a pyramid considered as an antenna. It is shown that due to the strong dispersion of the refractive index of the pyramid material, there will always be a part of the spectral range, in which the refractive index corresponds to the condition of electromagnetic wave localization (the photonic jet phenomenon). It is shown that the pyramid can simultaneously serve as a transmitting antenna both at the fundamental frequency and at multiple frequencies. Our consideration and approach are not limited only to the shape of the Cheops pyramid and can be generalized to all other shapes of known pyramids. It can be assumed that, despite the difference in the pyramid shapes throughout the world, such structures can play the role of antennas subject to the principle of mesoscale.
Keywords: pyramid, photonics, antenna.
V. Minin, O. V. Minin, and L. Yue
Russian Physics Journal, Vol. 62, No. 10, February, 2020 (Russian Original No. 10, October, 2019)