Effect of spontaneously generated coherence (SGC) on the line shapes of absorption, transparency, dispersion and group index of a four-level inverted Y-type atom–lasers coupling system

2021 ◽  
Vol 136 (7) ◽  
Author(s):  
Rohit Hazra ◽  
Md. Mabud Hossain
Keyword(s):  
Group Index ◽  
Spontaneously Generated Coherence ◽  
Line Shapes ◽  
Coupling System ◽  
Atom Lasers

Bistable behaviors of weak probe light via coherent and incoherent fields

2015 ◽  
Vol 93 (10) ◽  
pp. 1106-1111 ◽  
Author(s):  
H. Jafarzadeh ◽  
E. Ahmadi Sangachin ◽  
Seyyed Hossein Asadpour
Keyword(s):  
Optical Bistability ◽  
Light Propagation ◽  
Atomic System ◽  
Ring Cavity ◽  
Group Index ◽  
Probe Light ◽  
Spontaneously Generated Coherence ◽  
Intensity Threshold ◽  
Atomic Medium ◽  
Incoherent Pumping Field

In this paper, the bistable behaviors of weak probe light in a unidirectional ring cavity with a four-level atomic system are discussed. We find that in the presence of spontaneously generated coherence (SGC), the medium is completely phase dependent and the intensity threshold of optical bistability can be controlled. The effect of an incoherent pumping field on optical bistability in the presence and absence of SGC is also analyzed. Moreover, the group index behavior of weak probe light is investigated. We show that the intensity threshold of optical bistability can be controlled by light propagation switching from slow to fast by different parameters of the atomic medium.

Ultrastructural Localization of Acid Mucosubstance in Skeletal Muscle

1967 ◽  
Vol 25 ◽  
pp. 52-53 ◽  
Author(s):  
William J. Dougherty ◽  
Samuel S. Spicer
Keyword(s):  
Striated Muscle ◽  
Divalent Cations ◽  
Ultrastructural Localization ◽  
Major Elements ◽  
Frozen Sections ◽  
Thorium Dioxide ◽  
Iron Solution ◽  
Coupling System ◽  
Psoas Muscles ◽  
Formalin Fixed

In recent years, considerable attention has focused on the morphological nature of the excitation-contraction coupling system of striated muscle. Since the study of Porter and Palade, it has become evident that the sarcoplastic reticulum (SR) and transverse tubules constitute the major elements of this system. The problem still exists, however, of determining the mechamisms by which the signal to interdigitate is presented to the thick and thin myofilaments. This problem appears to center on the movement of Ca++ions between myofilaments and SR. Recently, Philpott and Goldstein reported acid mucosubstance associated with the SR of fish branchial muscle using the colloidal thorium dioxide technique, and suggested that this material may serve to bind or release divalent cations such as Ca++. In the present study, Hale's iron solution adapted to electron microscopy was applied to formalin-fixed myofibrils isolated from glycerol-extracted rabbit psoas muscles and to frozen sections of formalin-fixed rat psoas muscles.

H NMR Evidence for a Change in The Local Hydrogen Environment of Sites Associated with the Staebler-Wronski Effect in a-Si:H

2002 ◽  
Vol 715 ◽  
Author(s):  
T. Su ◽  
Robin Plachy ◽  
P. C. Taylor ◽  
S. Stone ◽  
G. Ganguly ◽  
...  
Keyword(s):  
Line Shape ◽  
Defect Density ◽  
Hydrogen Atoms ◽  
Hydrogen Environment ◽  
H Nmr ◽  
Line Shapes ◽  
Different Temperatures ◽  
Staebler Wronski Effect

AbstractWe study the H NMR line shapes of a sample of a-Si:H under several conditions: 1) as grown, 2) light-soaked for 600 hours, and 3) light-soaked followed by annealing at different temperatures. At T = 7 K, the NMR line shape of the sample after light soaking exhibits an additional doublet compared to that of the sample as-grown. This doublet is an indication of a closely separated hydrogen pair. The distance between the two hydrogen atoms is estimated to be about (2.3 ± 0.2) Å. The concentration of these hydrogen sites is estimated to be between 1017 and 1018 cm-3 consistent with ESR measurements of the defect density after light soaking. This doublet disappears after the sample is annealed at 200°C for 4 hours.

Thiol/Disulfide Homeostasis as an Early Biomarker to Differentiate Sepsis from Pneumonia in Intensive Care Units

2020 ◽  
Vol 23 ◽  
Author(s):  
Esra Cakir ◽  
Gamze Gok ◽  
Ozcan Erel ◽  
Isil Ozkocak Turan
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Early Period ◽  
Sepsis Group ◽  
Group Index ◽  
Total Thiol ◽  
Potential Biomarker ◽  
Early Biomarker ◽  
Index 2 ◽  
Research Period

Background: It is possible that patients with pneumonia also may have sepsis and the separation of these two clinical entities may induce some trouble to clinicians Objective: In order to separate a patient with pneumonia and a patient with sepsis, we qualify thiol/disulfide homeostasis as a potential biomarker. Method: This study designed between February 2018 – February 2019 prospectively. All patients in the intensive care unit with pneumonia and sepsis were enrolled in the study. At the time of hospitalization, thiol/disulfide homeostasis was measured. Patients diagnosed with sepsis and pneumonia were compared, in regards to thiol/disulfide homeostasis. Conclusion: In this study, we showed that thiol/disulfide homeostasis can be used as new markers in the early period in order to separate patients with sepsis and patients with pneumonia. Results: During research period, 103 patients with sepsis and 120 patients with pneumonia were enrolled into the study. When we compared native-thiol, total-thiol, and disulfide levels in both sepsis and pneumonia patients, we had similar results (p>0.05). In sepsis group, index-1 (disulfide/native thiol ratio) and index-2 (disulfide/total thiol ratio) were found out to be statistically higher than the pneumonia group, and index-3 (native thiol/total thiol ratio) was statistically lower than the pneumonia group (p=0.020, p= 0.021, p=0.021, respectively).

Testing the Planet Hypothesis: A Search for Variability in the Spectral‐Line Shapes of 51 Pegasi

1997 ◽  
Vol 478 (1) ◽  
pp. 374-380 ◽  
Author(s):  
Artie P. Hatzes ◽  
William D. Cochran ◽  
Christopher M. Johns‐Krull
Keyword(s):  
Spectral Line ◽  
Line Shapes
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