The effects of self-focusing on mood: A focus on two dimensions of the self (positive/negative)

AbstractAn analysis of the self-focusing of highly intense chirped pulse laser under exponential plasma density ramp with higher order value of axial electron temperature has been done. Beam width parameter is derived by using paraxial ray approximation and then solved numerically. It is seen that self-focusing of chirped pulse laser is intensely affected by the higher order values of axial electron temperature. Further, influence of exponential plasma density ramp is studied and it is concluded that self-focusing of laser enhances and occurs earlier. On the other hand defocusing of beam reduces to the great extent. It is noticed that the laser spot size reduces significantly under joint influence of the density ramp and the axial electron temperature. Present analysis may be useful for the analysis of quantum dots, the laser induced fusion and etc.

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Does Repeated Exposure to Critical Situations in a Screen-Based Simulation Improve the Self-Assessment of Non-Technical Skills in Postpartum Hemorrhage Management?

Simulation & Gaming ◽

10.1177/1046878119827324 ◽

2019 ◽

Vol 50 (2) ◽

pp. 102-123 ◽

Cited By ~ 5

Author(s):

Jessy Barré ◽

Daphné Michelet ◽

Anais Job ◽

Jennifer Truchot ◽

Philippe Cabon ◽

...

Keyword(s):

Postpartum Hemorrhage ◽

Technical Skills ◽

Two Dimensions ◽

Leadership Team ◽

Repeated Exposure ◽

The Self ◽

Self Assessment ◽

Team Working ◽

Simulation Session ◽

Nasa Tlx

Background. Postpartum hemorrhage (PPH) is the leading cause of maternal death in the world. Non-technical skills (e.g. communication) are now recognized as a contributing factor to medical safety. In the field of simulation, screen-based simulations are currently very popular with computer/technological development. This study evaluates a screen-based simulation device, PerinatSims, developed to improve technical and non-technical skills in PPH situation. This experiment hypothesized that exposure and repetition of training with PerinatSims would improve the self-assessment of non-technical skills, and therefore increase the ability to manage PPH. Methods. The primary endpoint was a self-assessment of non-technical skills during simulation session of PPH on a digital simulator. Twenty French midwives performed three of nine 25 minutes sessions of PPH screen-based simulation. Four self-assessment questionnaires were administered at the end of each simulation session: a leadership/team working questionnaire (BAT), a negative feelings/emotional questionnaire (DASS-21), a Flow questionnaire and a mental load questionnaire (NASA-TLX). Results between sessions were compared using a repeated measures ANOVA followed by a Bonferroni post hoc test. Results. The study showed a positive evolution during the three screen-based simulation sessions: an increase of leadership and team working self-assessment, an increase of Flow sense, and a decrease of negative emotions (anxiety and depression in the DASS-21 score). Significant decrease of stress was found only between the second and the third sessions, and significant differences in the NASA-TLX were observed only in two dimensions, Performance and Frustration. Conclusion. A repeated exposure to PPH situations with a screen-based simulation tool improved the midwives’ self-assessment, especially for leadership, team working, emotion management and Flow sense. Furthermore, midwives had a very positive feedback on the device. They highlighted the desire to use PerinatSims more often to be trained to PPH management, for technical as well as non-technical skills.

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Relativistic self-focusing of a rippled laser beam in a plasma

Journal of Plasma Physics ◽

10.1017/s0022377899008016 ◽

1999 ◽

Vol 62 (4) ◽

pp. 389-396 ◽

Cited By ~ 10

Author(s):

M. V. ASTHANA ◽

A. GIULIETTI ◽

DINESH VARSHNEY ◽

M. S. SODHA

Keyword(s):

Refractive Index ◽

Laser Beam ◽

The Self ◽

Laser Beams ◽

Radial Dependence ◽

Main Beam ◽

Gaussian Laser Beam ◽

Self Focusing ◽

Saturation Effects ◽

Paraxial Ray

This paper presents an analysis of the relativistic self-focusing of a rippled Gaussian laser beam in a plasma. Considering the nonlinearity as arising owing to relativistic variation of mass, and following the WKB and paraxial-ray approximations, the phenomenon of self-focusing of rippled laser beams is studied for arbitrary magnitude of nonlinearity. Pandey et al. [Phys. Fluids82, 1221 (1990)] have shown that a small ripple on the axis of the main beam grows very rapidly with distance of propagation as compared with the self-focusing of the main beam. Based on this analogy, we have analysed relativistic self-focusing of rippled beams in plasmas. The relativistic intensities with saturation effects of nonlinearity allow the nonlinear refractive index in the paraxial regime to have a slower radial dependence, and thus the ripple extracts relatively less energy from its neighbourhood.

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Pattern formation in a passive incoherent ring resonator system based on nonlinear material with the self-focusing non-instantaneous Kerr response

Optics & Laser Technology ◽

10.1016/j.optlastec.2011.08.003 ◽

2012 ◽

Vol 44 (3) ◽

pp. 505-513 ◽

Cited By ~ 3

Author(s):

M.K. Maurya ◽

R.A. Yadav

Keyword(s):

Pattern Formation ◽

Ring Resonator ◽

The Self ◽

Nonlinear Material ◽

Self Focusing ◽

Resonator System

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Deformation of a liquid surface by laser heating: laser-beam self-focusing and generation of capillary waves

Canadian Journal of Physics ◽

10.1139/p86-235 ◽

1986 ◽

Vol 64 (9) ◽

pp. 1341-1344 ◽

Cited By ~ 10

Author(s):

J. Hartikainen ◽

J. Jaarinen ◽

M. Luukkala

Keyword(s):

Laser Beam ◽

Laser Heating ◽

Surface Deformation ◽

Liquid Surface ◽

Capillary Waves ◽

The Self ◽

Self Focusing

The surface deformation of oil by laser heating is presented. The self-focusing of the reflected beam and the generation of capillary waves are observed.

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Generation of Efficient Terahertz Radiation by Relativistic Self-Focusing of A Cosh-Gaussian Laser Beam in A Magnetized Plasma

10.21203/rs.3.rs-1195824/v1 ◽

2021 ◽

Author(s):

Gunjan Purohit ◽

Bineet Gaur ◽

Pradeep Kothiyal ◽

Amita Raizada

Keyword(s):

Laser Beam ◽

Numerical Study ◽

The Self ◽

Magnetized Plasma ◽

Thz Radiation ◽

Gaussian Laser Beam ◽

Plasma Parameters ◽

Gaussian Profile ◽

Self Focusing ◽

Incident Laser Intensity

Abstract This paper presents a scheme for the generation of terahertz (THz) radiation by self-focusing of a cosh-Gaussian laser beam in the magnetized and rippled density plasma, when relativistic nonlinearity is operative. The strong coupling between self-focused laser beam and pre-existing density ripple produces nonlinear current that originates THz radiation. THz radiation is produced by the interaction of the cosh-Gaussian laser beam with electron plasma wave under the appropriate phase matching conditions. Expressions for the beamwidth parameter of cosh-Gaussian laser beam and the electric vector of the THz radiation have been obtained using higher-order paraxial theory and solved numerically. The self-focusing of the cosh-Gaussian laser beam and its effect on the generated THz amplitude have been studied for specific laser and plasma parameters. Numerical study has been performed on various values of the decentered parameter, incident laser intensity, magnetic field, and relative density. The results have also been compared with the paraxial region as well as the Gaussian profile of laser beam. Numerical results suggest that the self-focusing of the cosh-Gaussian laser beam and the amplitude of THz radiation increase in the extended paraxial region compared to the paraxial region. It is also observed that the focusing of the cosh-Gaussian laser beam in the magnetized plasma and the amplitude of the THz radiation increases at higher values of the decentered parameter.

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