From Single-Channel Recordings to Brain-Mapping Devices: The Impact of Electroencephalography on Experimental Psychology.

2005 ◽  
Vol 8 (1) ◽  
pp. 95-117 ◽  
Author(s):  
Frank Rösler
2012 ◽  
Vol 4 (1) ◽  
pp. 2-7 ◽  
Author(s):  
Azusa Oshima ◽  
Ayumi Hirano-Iwata ◽  
Tomohiro Nasu ◽  
Yasuo Kimura ◽  
Michio Niwano

1997 ◽  
Vol 273 (2) ◽  
pp. H796-H804 ◽  
Author(s):  
C. Valdivia ◽  
J. O. Hegge ◽  
R. D. Lasley ◽  
H. H. Valdivia ◽  
R. Mentzer

We investigated the effects of myocardial stunning on the function of the two main Ca2+ transport proteins of the sarcoplasmic reticulum (SR), the Ca(2+)-adenosinetriphosphatase and the Ca(2+)-release channel or ryanodine receptor. Regional myocardial stunning was induced in open-chest pigs (n = 6) by a 10-min occlusion of the left anterior descending coronary artery (LAD) and 2 h reperfusion. SR vesicles isolated from the LAD-perfused region (stunned) and the normal left circumflex coronary artery (LC)-perfused region were used to assess the oxalate-supported 45Ca2+ uptake, [3H]ryanodine binding, and single-channel recordings of ryanodine-sensitive Ca(2+)-release channels in planar lipid bilayers. Myocardial stunning decreased LAD systolic wall thickening to 20% of preischemic values. The rate of SR 45Ca2+ uptake in the stunned LAD bed was reduced by 37% compared with that of the normal LC bed (P < 0.05). Stunning was also associated with a 38% reduction in the maximal density of high-affinity [3H]ryanodine binding sites (P < 0.05 vs. normal LC) but had no effect on the dissociation constant. The open probability of ryanodine-sensitive Ca(2+)-release channels determined by single channel recordings in planar lipid bilayers was 26 +/- 2% for control SR (n = 33 channels from 3 animals) and 14 +/- 2% for stunned SR (n = 21 channels; P < 0.05). This depressed activity of SR function observed in postischemic myocardium could be one of the mechanisms underlying myocardial stunning.


Author(s):  
M. K. Firozjaei ◽  
M. Makki ◽  
J. Lentschke ◽  
M. Kiavarz ◽  
S. K. Alavipanah

Abstract. Spatiotemporal mapping and modeling of Land Surface Temperature (LST) variations and characterization of parameters affecting these variations are of great importance in various environmental studies. The aim of this study is a spatiotemporal modeling the impact of surface characteristics variations on LST variations for the studied area in Samalghan Valley. For this purpose, a set of satellite imagery and meteorological data measured at the synoptic station during 1988–2018, were used. First, single-channel algorithm, Tasseled Cap Transformation (TCT) and Biophysical Composition Index (BCI) were employed to estimate LST and surface biophysical parameters including brightness, greenness and wetness and BCI. Also, spatial modeling was used to modeling of terrain parameters including slope, aspect and local incident angle based on DEM. Finally, the principal component analysis (PCA) and the Partial Least Squares Regression (PLSR) were used to modeling and investigate the impact of surface characteristics variations on LST variations. The results indicated that surface characteristics vary significantly for case study in spatial and temporal dimensions. The correlation coefficient between the PC1 of LST and PC1s of brightness, greenness, wetness, BCI, DEM, and solar local incident angle were 0.65, −0.67, −0.56, 0.72, −0.43 and 0.53, respectively. Furthermore, the coefficient coefficient and RMSE between the observed LST variation and modelled LST variation based on PC1s of brightness, greenness, wetness, BCI, DEM, and local incident angle were 0.83 and 0.14, respectively. The results of study indicated the LST variation is a function of s terrain and surface biophysical parameters variations.


Biochemistry ◽  
1983 ◽  
Vol 22 (10) ◽  
pp. 2319-2323 ◽  
Author(s):  
Benjamin A. Suarez-Isla ◽  
Kee Wan ◽  
Jon Lindstrom ◽  
Mauricio Montal

2017 ◽  
Author(s):  
Hector Gomez ◽  
Usama Tohid ◽  
Arturo Pacheco-Vega

In this study, numerical simulations were performed to find the current-voltage distribution for a laminar flow-based membraneless fuel cell (LFFC). The system uses formic acid and oxygen as the fuel and oxidant, respectively, and has a Y-shaped geometry with two separate inlets that merge into a single channel. The main objective of this work is to analyze the impact of geometry and operating conditions on the performance of these devices. This is done by proposing a novel wavy-channel-based geometry for the side walls, along with planar top and bottom walls, and comparing the behavior of the corresponding system to that of LFFCs based on straight-channel walls. Special attention is placed on the effect of both the amplitude of the sinusoid and its wavelength on the performance of the device. The effect of flow rates — in the range of [200, 350] μL/min — is also studied. The mathematical model is formulated by considering the Navier-Stokes equations along with Butler-Volmer and Fick’s law. For each fuel-cell configuration, the governing equations are discretized and solved using finite elements, and the solutions given in terms of the polarization curves. The model was first verified using published numerical data for a straight-channel-based LFFC. The simulations show that the performance achieved by the device, based on the proposed wavy channel geometry, is slightly better than that of the LFFC with straight channel walls. On the other hand, higher flowrates significantly improve the power density of the device. Although the current mathematical model may be useful in a variety of applications, improvements on it are currently underway to account for the effects of potential distributions on ions within the flow channel, and results from it will be reported in the future.


2019 ◽  
Vol 131 (2) ◽  
pp. 474-480 ◽  
Author(s):  
Guglielmo Puglisi ◽  
Tommaso Sciortino ◽  
Marco Rossi ◽  
Antonella Leonetti ◽  
Luca Fornia ◽  
...  

OBJECTIVEThe goal of surgery for gliomas is maximal tumor removal while preserving the patient’s full functional integrity. At present during frontal tumor removal, this goal is mostly achieved, although the risk of impairing the executive functions (EFs), and thus the quality of life, remains significant. The authors investigated the accuracy of an intraoperative version of the Stroop task (iST), adapted for intraoperative mapping, to detect EF-related brain sites by evaluating the impact of the iST brain mapping on preserving functional integrity following a maximal tumor resection.METHODSForty-five patients with nondominant frontal gliomas underwent awake surgery; brain mapping was used to establish the functional boundaries for the resection. In 18 patients language, praxis, and motor functions, but not EFs (control group), were mapped intraoperatively at the cortical-subcortical level. In 27 patients, in addition to language, praxis, and motor functions, EFs were mapped with the iST at the cortical-subcortical level (Stroop group). In both groups the EF performance was evaluated preoperatively, at 7 days and 3 months after surgery.RESULTSThe iST was successfully administered in all patients. Consistent interferences, such as color-word inversion/latency, were obtained by stimulating precise white matter sites below the inferior and middle frontal gyri, anterior to the insula and over the putamen, and these were used to establish the posterior functional limit of the resection. Procedures implemented with iST dramatically reduced the EF deficits at 3 months. The EOR was similar in Stroop and control groups.CONCLUSIONSBrain mapping with the iST allows identification and preservation of the frontal lobe structures involved in inhibition of automatic responses, reducing the incidence of postoperative EF deficits and enhancing the further posterior and inferior margin of tumor resection.


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