A new narrow band of highly correlated electrons in oxide superconductors

1989 ◽  
Vol 71 (10) ◽  
pp. 829-833 ◽  
Author(s):  
H. Matsumoto ◽  
M. Sasaki ◽  
M. Tachiki
Keyword(s):  
Narrow Band ◽  
Oxide Superconductors ◽  
Correlated Electrons ◽  
Highly Correlated

Vegetation–soil relationships along a spruce forest transect in interior Alaska

1979 ◽  
Vol 57 (23) ◽  
pp. 2644-2656 ◽  
Author(s):  
C. T. Dyrness ◽  
D. F. Grigal
Keyword(s):  
Forest Floor ◽  
Narrow Band ◽  
Black Spruce ◽  
White Spruce ◽  
Spruce Forest ◽  
Forest Communities ◽  
Soil Series ◽  
Highly Correlated ◽  
Forest Transect ◽  
Upper Slope

Five distinct forest communities were recognized along a 3-km transect. These are, listed in order of decreasing elevation: (i) open black spruce/feathermoss - Cladonia, (ii) closed black spruce/feathermoss, (iii) open black spruce/Sphagnum, (iv) black spruce woodland/Eriophorum, and (v) white spruce/alder/Calamagrostis (restricted to a narrow band adjacent to a stream). Several techniques of ordination were used to recognize these five forest communities plus two intergrades: (open black spruce/feathermoss - Cladonia) - (Sphagnum) and open black spruce/Sphagnum - woodland/Eriophorum.The distribution of two-thirds of the plant species was highly correlated with vegetation–slope zones. Results of the fit of Gaussian curves also suggest that vegetation boundaries were well placed. The distribution of the four soil series in the area was well correlated with vegetation–slope zones: three were limited to one zone each. Permafrost, absent from the soil on the ridgetop and upper slope, was generally within 40 to 50 cm of the surface elsewhere and tended to be at shallower depths as elevation decreased. The most striking differences in forest floor properties were found in the white spruce zone compared with the six black spruce dominated zones. The white spruce forest floor was markedly thinner and had higher levels of nutrients. In the six black spruce dominated zones, forest floor thickness and concentrations of N and Mg tended to increase with distance downslope, and P and K decreased.

Effective Hamiltonian of oxide superconductors and a narrow band near the Fermi level

1990 ◽  
Vol 42 (16) ◽  
pp. 10041-10051 ◽  
Author(s):  
S. Ishihara ◽  
H. Matsumoto ◽  
M. Tachiki
Keyword(s):  
Fermi Level ◽  
Narrow Band ◽  
Oxide Superconductors ◽  
Effective Hamiltonian

scholarly journals Stimulus-induced narrow-band gamma oscillations in humans can be recorded using open-hardware low-cost EEG amplifier

2021 ◽  
Author(s):  
Srividya Pattisapu ◽  
Supratim Ray
Keyword(s):  
Narrow Band ◽  
Low Cost ◽  
Low Frequency ◽  
Gamma Oscillations ◽  
Open Hardware ◽  
Full Screen ◽  
Research Grade ◽  
Highly Correlated ◽  
Almost All ◽  
Temporal Profiles

Stimulus-induced narrow-band gamma oscillations (30-70 Hz) in human electro - encephalograph (EEG) have been linked to attentional and memory mechanisms and are abnormal in mental health conditions such as autism, schizophrenia and Alzheimer's Disease. This suggests that gamma oscillations could be valuable both as a research tool and an inexpensive, non-invasive biomarker for disease evaluation. However, since the absolute power in EEG decreases rapidly with increasing frequency following a "1/f" power law, and the gamma band includes line noise frequency, these oscillations are highly susceptible to instrument noise. Previous studies that recorded stimulus-induced gamma oscillations used expensive research-grade EEG amplifiers to address this issue. While low-cost EEG amplifiers have become popular in Brain Computer Interface applications that mainly rely on low-frequency oscillations (<30 Hz) or steady-state-visually-evoked-potentials, whether they can also be used to measure stimulus-induced gamma oscillations is unknown. We recorded EEG signals using a low-cost, open-source amplifier (OpenBCI) and a traditional, research-grade amplifier (Brain Products GmbH) in male (N = 6) and female (N = 5) subjects (22-29 years) while they viewed full-screen static gratings that are known to induce gamma oscillations. OpenBCI recordings showed gamma response in almost all the subjects who showed a gamma response in Brain Products recordings, and the spectral and temporal profiles of these responses in alpha (8-13 Hz) and gamma bands were highly correlated between OpenBCI and Brain Products recordings. These results suggest that low-cost amplifiers can potentially be used in stimulus induced gamma response detection, making its research, and application in medicine more accessible.

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