A STUDY ON COGNITIVE RESPONSE TENDENCY AND DAMAGE THRESHOLD OF ABSORBING MEDIUM BY LASER-INDUCED INDIRECT STIMULATION

Laser-based research can be used in biology, medicine, engineering and many other industries. The use of pulsed laser can induce thermoelastic effect in a short time and give mechanical stimulation to the human body. When the elastic medium is attached to the human body and the laser is irradiated, the mechanical stimulus induced in the elastic medium can be transferred to the human body, which may cause tactile sensation. In this study, we investigated the effects of laser-induced indirect stimulation on cognitive response and damage to absorbing medium. Through the human body experiment, we studied the laser parameter condition that most subjects feel touch. In addition, thermal analysis simulations were performed to predict the condition of the laser pulse energy, the laser frequency and the temperature at the damage threshold of the absorption medium. The results of this study are expected to be useful for conducting non-contact tactile sensation using laser, and this technique can be widely used in laser biomedical stimulation, haptic technology, and other biological and medical fields.

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Mid-Air Tactile Sensations Evoked by Laser-Induced Plasma: A Neurophysiological Study

Frontiers in Neuroscience ◽

10.3389/fnins.2021.733423 ◽

2021 ◽

Vol 15 ◽

Author(s):

Hyung-Sik Kim ◽

Kyu Beom Kim ◽

Je-Hyeop Lee ◽

Jin-Ju Jung ◽

Ye-Jin Kim ◽

...

Keyword(s):

Mechanical Stimulus ◽

Tactile Sensation ◽

Classification Error ◽

Mechanical Stimuli ◽

Long Distance ◽

Laser Induced Plasma ◽

Sensorimotor Area ◽

Stimulation Method ◽

Haptic Stimulation ◽

Plasma Effect

This study demonstrates the feasibility of a mid-air means of haptic stimulation at a long distance using the plasma effect induced by laser. We hypothesize that the stress wave generated by laser-induced plasma in the air can propagate through the air to reach the nearby human skin and evoke tactile sensation. To validate this hypothesis, we investigated somatosensory responses in the human brain to laser plasma stimuli by analyzing electroencephalography (EEG) in 14 participants. Three types of stimuli were provided to the index finger: a plasma stimulus induced from the laser, a mechanical stimulus transferred through Styrofoam stick, and a sham stimulus providing only the sound of the plasma and mechanical stimuli at the same time. The event-related desynchronization/synchronization (ERD/S) of sensorimotor rhythms (SMRs) in EEG was analyzed. Every participant verbally reported that they could feel a soft tap on the finger in response to the laser stimulus, but not to the sham stimulus. The spectrogram of EEG evoked by laser stimulation was similar to that evoked by mechanical stimulation; alpha ERD and beta ERS were present over the sensorimotor area in response to laser as well as mechanical stimuli. A decoding analysis revealed that classification error increased when discriminating ERD/S patterns between laser and mechanical stimuli, compared to the case of discriminating between laser and sham, or mechanical and sham stimuli. Our neurophysiological results confirm that tactile sensation can be evoked by the plasma effect induced by laser in the air, which may provide a mid-air haptic stimulation method.

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Tactile sensation transmission from a robotic arm to the human body via a haptic interface

2015 IEEE World Haptics Conference (WHC) ◽

10.1109/whc.2015.7177704 ◽

2015 ◽

Cited By ~ 3

Author(s):

M. Reza Motamedi ◽

Jean-Philippe Roberge ◽

Vincent Duchaine

Keyword(s):

Human Body ◽

Haptic Interface ◽

Robotic Arm ◽

Tactile Sensation

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Microstructural comparison of synthetic bioceramics with natural bioceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084491 ◽

1991 ◽

Vol 49 ◽

pp. 38-39

Author(s):

Shulin Wen ◽

Jingwei Feng ◽

A. Krajewski ◽

A. Ravaglioli

Keyword(s):

Recent Work ◽

Human Body ◽

Human Tissues ◽

Main Constituent ◽

Laboratory Furnace ◽

Chinese Adult ◽

Human Enamel ◽

Biological Compatibility ◽

Synthetic Hydroxyapatite ◽

Synthetic Work

Hydroxyapatite bioceramics has attracted many material scientists as it is the main constituent of the bone and the teeth in human body. The synthesis of the bioceramics has been performed for years. Nowadays, the synthetic work is not only focused on the hydroapatite but also on the fluorapatite and chlorapatite bioceramics since later materials have also biological compatibility with human tissues; and they may also be very promising for clinic purpose. However, in comparison of the synthetic bioceramics with natural one on microstructure, a great differences were observed according to our previous results. We have investigated these differences further in this work since they are very important to appraise the synthetic bioceramics for their clinic application.The synthetic hydroxyapatite and chlorapatite were prepared according to A. Krajewski and A. Ravaglioli and their recent work. The briquettes from different hydroxyapatite or chlorapatite powders were fired in a laboratory furnace at the temperature of 900-1300°C. The samples of human enamel selected for the comparison with synthetic bioceramics were from Chinese adult teeth.

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The observation of nano-voids in Au thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126627 ◽

1987 ◽

Vol 45 ◽

pp. 366-367

Author(s):

William Krakow

Keyword(s):

Thin Films ◽

Melting Point ◽

Present Author ◽

Stacking Faults ◽

Damage Threshold ◽

Ionic Species ◽

Rare Gases ◽

Chain Defects ◽

Vacancy Chains ◽

Au Thin Films

It has long been known that defects such as stacking faults and voids can be quenched from various alloyed metals heated to near their melting point. Today it is common practice to irradiate samples with various ionic species of rare gases which also form voids containing solidified phases of the same atomic species, e.g. ref. 3. Equivalently, electron irradiation has been used to produce damage events, e.g. ref. 4. Generally all of the above mentioned studies have relied on diffraction contrast to observe the defects produced down to a dimension of perhaps 10 to 20Å. Also all these studies have used ions or electrons which exceeded the damage threshold for knockon events. In the case of higher resolution studies the present author has identified vacancy and interstitial type chain defects in ion irradiated Si and was able to identify both di-interstitial and di-vacancy chains running through the foil.

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Study on erythrocytes by SEM photogrammetry (SEMP) technique

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161187 ◽

1990 ◽

Vol 48 (3) ◽

pp. 724-725

Author(s):

Tong Wensheng ◽

Lu Lianhuang ◽

Zhang Zhijun

Keyword(s):

Quantitative Analysis ◽

Cell Membrane ◽

Clinical Diagnosis ◽

Human Body ◽

Blood Cells ◽

Three Dimensional ◽

Normal Person ◽

Blood Disease ◽

Computation Technique ◽

Important Basis

This is a combined study of two diffirent branches, photogrammetry and morphology of blood cells. The three dimensional quantitative analysis of erythrocytes using SEMP technique, electron computation technique and photogrammetry theory has made it possible to push the study of mophology of blood cells from LM, TEM, SEM to a higher stage, that of SEM P. A new path has been broken for deeply study of morphology of blood cells.In medical view, the abnormality of the quality and quantity of erythrocytes is one of the important changes of blood disease. It shows the abnormal blood—making function of the human body. Therefore, the study of the change of shape on erythrocytes is the indispensable and important basis of reference in the clinical diagnosis and research of blood disease.The erythrocytes of one normal person, three PNH Patients and one AA patient were used in this experiment. This research determines the following items: Height;Length of two axes (long and short), ratio; Crevice in depth and width of cell membrane; Circumference of erythrocytes; Isoline map of erythrocytes; Section map of erythrocytes.

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Environmental cell studies of deformation and fracture

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175715 ◽

1990 ◽

Vol 48 (4) ◽

pp. 516-517

Author(s):

H. K. Birnbaum ◽

I. M. Robertson

Keyword(s):

National Laboratory ◽

Argonne National Laboratory ◽

Damage Threshold ◽

Chromatic Aberration ◽

Good Choice ◽

Point Of View ◽

Deformation And Fracture ◽

Environmental Cell ◽

Gas Molecules ◽

The University

Studies of the effects of hydrogen environments on the deformation and fracture of fcc, bcc and hep metals and alloys have been carried out in a TEM environmental cell. The initial experiments were performed in the environmental cell of the HVEM facility at Argonne National Laboratory. More recently, a dedicated environmental cell facility has been constructed at the University of Illinois using a JEOL 4000EX and has been used for these studies. In the present paper we will describe the general design features of the JEOL environmental cell and some of the observations we have made on hydrogen effects on deformation and fracture.The JEOL environmental cell is designed to operate at 400 keV and below; in part because of the available accelerating voltage of the microscope and in part because the damage threshold of most materials is below 400 keV. The gas pressure at which chromatic aberration due to electron scattering from the gas molecules becomes excessive does not increase rapidly with with accelerating voltage making 400 keV a good choice from that point of view as well. A series of apertures were placed above and below the cell to control the pressures in various parts of the column.

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