335 research outputs found
REM Rebound Effect
Sleep is a state consisting of several different stages of reversible disconnection from the environment with accompanying reduced consciousness, atonia, and metabolic changes. These stages are primarily divided into rapid-eye-movement (REM) sleep, which is characterized by classic ocular saccadic movement and fast-wave EEG patterns reminiscent of wakefulness, and non-rapid-eye movement (NREM) which can be subdivided further into three stages each distinguished by distinct EEG wave patterns. Normally an individual will progress through a predictable cycle of stages beginning with wakefulness, then through each stage of NREM sleep before quickly reversing through the stages to enter REM sleep.
The maintenance of appropriate sleep architecture appears to play an important role in promoting physiological and mental health. Such health benefits may include modulating memory, emotion, and cognitive integration of stressors and mechanisms are in place to restore sleep homeostasis if sleep is disrupted. One of these mechanisms is REM rebound, which refers to the compensatory increase of the frequency, depth, and intensity of rapid-eye-movement (REM) sleep following sleep deprivation or significant stressors. Several experimental studies utilizing EEG and hormonal measurements have illustrated that human and animal participants who experience sleep deprivation or significant stressors will experience increased frequency and intensity of REM sleep to compensate for said deprivation
Using the EBUS Scope in the Esophagus
This chapter aims at introducing the interested Pulmonologist/Interventional Pulmonologist to the esophageal ultrasound. In this chapter, we give short descriptions of some technical aspects of the endobronchial ultrasound (EBUS) scope and explain in detail why we believe the EBUS scope is well suited to be an esophageal scope in the hands of the trained pulmonologist. The chapter then explains indications and benefits of this procedure that we consider central to the practice of chest physicians. We also describe in steps how to reach each lymph node station using the EBUS scope as a EUS scope (EUS-B) from our own experience. Procedurerelated complications and contraindications are also described
EUS-B for the Interventional Pulmonologist Using the EBUS Scope in the Esophagus
This chapter aims at introducing the interested Pulmonologist/Interventional Pulmonologist to the esophageal ultrasound. In this chapter, we give short descriptions of some technical aspects of the endobronchial ultrasound (EBUS) scope and explain in detail why we believe the EBUS scope is well suited to be an esophageal scope in the hands of the trained pulmonologist. The chapter then explains indications and benefits of this procedure that we consider central to the practice of chest physicians. We also describe in steps how to reach each lymph node station using the EBUS scope as a EUS scope (EUS-B) from our own experience. Procedure-related complications and contraindications are also described
Study of vibrational spectra of polycyclic aromatic hydrocarbons with phenyl side group
Computational study of polycyclic aromatic hydrocarbons (PAHs) with phenyl
side group substituted at different positions is reported. The infrared
spectral variations due to the position of phenyl substitution, ionization
state and the size of the molecules are discussed and possible contribution of
phenyl-PAHs to the mid-infrared emission features from astrophysical objects is
analyzed. Structurally phenyl group substitution at 2nd position gives more
stable species compared to substitution at other positions. Phenyl-PAHs exhibit
new aromatic bands near 695 and 741 cm (14.4 and 13.5 m), due to
contribution from quintet C-H wag, that compare well with minor features at
14.2 and 13.5 m observed in several astrophysical objects. Just as in
plain PAHs, the C-C stretch vibrational modes (1600 cm) have
negligible intensity in neutrals, but the cations of all phenyl-PAHs exhibit
significantly strong phenyl group C-C stretch peak close to class B type 6.2
m astrophysical band. In 2-phenylpyrene, it is the neutral molecule that
exhibits this strong feature in the 6.2 m range along with other features
that match with sub-features at 6.66 and 6.9 m, observed in astronomical
spectra of some late type objects. The substitution of phenyl side group at
solo position shifts the C-C stretch mode of parent PAH close to the region of
6.2 m astrophysical band. The results indicate possibility of phenyl-PAHs
in space and the bottom-up formation of medium sized compact PAHs with phenyl
side group in carbon rich cool circumstellar shells. Phenyl-PAHs need to be
considered in modelling mid-infrared emission spectra of various astrophysical
objects.Comment: 45 papges including 15 Figures and 3 Table
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