Infant Thresholds with Enhanced Attention to the Signal in Visual Reinforcement Audiometry

1988 ◽  
Vol 31 (3) ◽  
pp. 480-484 ◽  
Author(s):  
Michael A. Primus
Keyword(s):  
Experimental Data ◽  
Modified Technique ◽  
Auditory Thresholds ◽  
Visual Reinforcement ◽  
Adult Performance ◽  
Attentional Effect ◽  
Threshold Procedure ◽  
Infant Attention ◽  
Operant Procedure ◽  
Attentional Behavior

Experimental data show a discrepancy between adult auditory thresholds and best estimates of infant thresholds. The source of the discrepancy has not been determined. Attentional differences between infants and adults and procedural differences to accommodate infant attentional behavior may account at least in part for the discrepancy. A standard operant procedure, Visual Reinforcement Audiometry (VRA), was modified to enhance infant attention to impending auditory signals. Results on 16 infants evaluated with conventional VRA and modified VRA revealed an average 5.5 dB improvement in threshold with the modified technique. Correction for adult performance in similar tasks indicated a 3.3 dB attentional effect between infant and adult thresholds. The shift in threshold reflects on the adequacy Of VRA as a threshold procedure.

scholarly journals Experimental study of amphibole crystallization from the highly magnesian melt of Shiveluch volcano

2019 ◽  
Vol 27 (5) ◽  
pp. 476-495 ◽  
Author(s):  
A. G. Simakin ◽  
V. N. Devyatova ◽  
T. P. Salova ◽  
O. Yu. Shaposhnikova
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Oxygen Fugacity ◽  
Volcanic Rocks ◽  
Maximum Size ◽  
Rapid Quenching ◽  
Shiveluch Volcano ◽  
Modified Technique ◽  
Before And After ◽  
Partial Transfer

The paper reports results of an experimental study of amphibole crystallization from the highly magnesian andesite melt of Shiveluch volcano, Kamchatka. The experiments were carried out in IHPV at 300 MPa and 940–980°С in iron-saturated platinum capsules, using rapid quenching and temperature oscillations (in some experiments). The redox state of iron in the system was measured before and after the experiments using Mössbauer spectroscopy. The maximum size of the experimental amphibole crystals (up to 200 μm) was close to those of natural amphibole phenocrysts in the volcanic rocks of Shiveluch volcano. The experimental data show that the content of octahedrally coordinated Al (Al6) in the amphibole considerably varies with small variations in the intensive parameters (P, T, and fO2) and composition of the melt, and the maximum Al6 concentration can be evaluated only by using a reasonably large dataset of amphibole analyses. A modified 13eCNK method is suggested to calculate the values of Al6 and Fe3+/Fe2+ with regard for the Ti concentration and the probable partial transfer of Mg into site B in high-Mg amphibole. Calculations with this modified technique yield lower Fe3+/Fe2+ and higher Al6 values. Our experimental data show that the temperature of amphibole liquidus crystallization decreases from about 990 to 960°C when the oxygen fugacity drops from NNO + 1.5 to NNO + 0.4. In view of this, the transition from amphibole-bearing to anhydrous mineral assemblage in the magmas of Shiveluch volcano might have been caused by variations of the oxygen fugacity but not water. The application of our geobarometer to amphiboles from Shiveluch volcano (extrusions Krasnaya and Karan) yields the highest pressure estimate of above 1 GPa, corresponding to the P-T conditions of the melting of garnet-bearing amphibolite in the lower crust.

Microanatomy of the Periplasm of Bacillus Licheniformis

1971 ◽  
Vol 29 ◽  
pp. 262-263
Author(s):  
B.K. Ghosh
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Bacillus Licheniformis ◽  
External Environment ◽  
Permeability Barrier ◽  
Periplasmic Space ◽  
Modified Technique ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.

Microdiffraction Patterns of Small Metallic Particles II; Theoretical Analysis

1982 ◽  
Vol 40 ◽  
pp. 668-669
Author(s):  
A. Gómez ◽  
P. Schabes-Retchkiman ◽  
M. José-Yacamán ◽  
T. Ocaña
Keyword(s):  
Experimental Data ◽  
Electron Diffraction ◽  
Theoretical Analysis ◽  
Size Range ◽  
Dynamical Theory ◽  
Metallic Particles ◽  
Splitting Effect

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

Evidence for ordered Fe3Ni

1987 ◽  
Vol 45 ◽  
pp. 216-217
Author(s):  
K.B. Reuter ◽  
D.B. Williams ◽  
J.I. Goldstein
Keyword(s):  
Experimental Data ◽  
Martensitic Transformation ◽  
Electron Diffraction ◽  
Room Temperature ◽  
Direct Evidence ◽  
Transformation Product ◽  
Iron Meteorites ◽  
X Ray ◽  
Ni Content ◽  
Temperature Transformation

In the Fe-Ni system, although ordered FeNi and ordered Ni3Fe are experimentally well established, direct evidence for ordered Fe3Ni is unconvincing. Little experimental data for Fe3Ni exists because diffusion is sluggish at temperatures below 400°C and because alloys containing less than 29 wt% Ni undergo a martensitic transformation at room temperature. Fe-Ni phases in iron meteorites were examined in this study because iron meteorites have cooled at slow rates of about 10°C/106 years, allowing phase transformations below 400°C to occur. One low temperature transformation product, called clear taenite 2 (CT2), was of particular interest because it contains less than 30 wtZ Ni and is not martensitic. Because CT2 is only a few microns in size, the structure and Ni content were determined through electron diffraction and x-ray microanalysis. A Philips EM400T operated at 120 kV, equipped with a Tracor Northern 2000 multichannel analyzer, was used.

EELS white line intensities calculated for the 3d and 4d metals

1989 ◽  
Vol 47 ◽  
pp. 388-389
Author(s):  
C. C. Ahn ◽  
D. H. Pearson ◽  
P. Rez ◽  
B. Fultz
Keyword(s):  
Experimental Data ◽  
Line Intensity ◽  
Transition Probabilities ◽  
Initial Increase ◽  
White Line ◽  
Hartree Fock ◽  
Line Intensities ◽  
Integrated Intensity ◽  
X Ray Absorption ◽  
The Continuum

Previous experimental measurements of the total white line intensities from L2,3 energy loss spectra of 3d transition metals reported a linear dependence of the white line intensity on 3d occupancy. These results are inconsistent, however, with behavior inferred from relativistic one electron Dirac-Fock calculations, which show an initial increase followed by a decrease of total white line intensity across the 3d series. This inconsistency with experimental data is especially puzzling in light of work by Thole, et al., which successfully calculates x-ray absorption spectra of the lanthanide M4,5 white lines by employing a less rigorous Hartree-Fock calculation with relativistic corrections based on the work of Cowan. When restricted to transitions allowed by dipole selection rules, the calculated spectra of the lanthanide M4,5 white lines show a decreasing intensity as a function of Z that was consistent with the available experimental data.Here we report the results of Dirac-Fock calculations of the L2,3 white lines of the 3d and 4d elements, and compare the results to the experimental work of Pearson et al. In a previous study, similar calculations helped to account for the non-statistical behavior of L3/L2 ratios of the 3d metals. We assumed that all metals had a single 4s electron. Because these calculations provide absolute transition probabilities, to compare the calculated white line intensities to the experimental data, we normalized the calculated intensities to the intensity of the continuum above the L3 edges. The continuum intensity was obtained by Hartree-Slater calculations, and the normalization factor for the white line intensities was the integrated intensity in an energy window of fixed width and position above the L3 edge of each element.

Race Difference in Auditory Sensitivity

1964 ◽  
Vol 7 (4) ◽  
pp. 389-393 ◽  
Author(s):  
David C. Shepherd ◽  
Robert Goldstein ◽  
Benjamin Rosenblüt
Keyword(s):  
White Women ◽  
White Men ◽  
Sensitivity Study ◽  
Auditory Sensitivity ◽  
Race Difference ◽  
Men And Women ◽  
Auditory Thresholds ◽  
Békésy Audiometry ◽  
Method Of Adjustment ◽  
Better Than

Two separate studies investigated race and sex differences in normal auditory sensitivity. Study I measured thresholds at 500, 1000, and 2000 cps of 23 white men, 26 white women, 21 negro men, and 24 negro women using the method of limits. In Study II thresholds of 10 white men, 10 white women, 10 negro men, and 10 negro women were measured at 1000 cps using four different stimulus conditions and the method of adjustment by means of Bekesy audiometry. Results indicated that the white men and women in Study I heard significantly better than their negro counterparts at 1000 and 2000 cps. There were no significant differences between the average thresholds measured at 1000 cps of the white and negro men in Study II. White women produced better auditory thresholds with three stimulus conditions and significantly more sensitive thresholds with the slow pulsed stimulus than did the negro women in Study II.

A fuzzy neural network approach for modeling the growth kinetics of FeB and Fe2B layers during the boronizing process

2018 ◽  
Vol 106 (6) ◽  
pp. 603 ◽  
Author(s):  
Bendaoud Mebarek ◽  
Mourad Keddam
Keyword(s):  
Neural Network ◽  
Experimental Data ◽  
Fuzzy Neural Network ◽  
Treatment Time ◽  
Calculation Model ◽  
Average Error ◽  
Network Approach ◽  
Neural Network Approach ◽  
Fuzzy Neural ◽  
Kinetics Of

In this paper, we develop a boronizing process simulation model based on fuzzy neural network (FNN) approach for estimating the thickness of the FeB and Fe2B layers. The model represents a synthesis of two artificial intelligence techniques; the fuzzy logic and the neural network. Characteristics of the fuzzy neural network approach for the modelling of boronizing process are presented in this study. In order to validate the results of our calculation model, we have used the learning base of experimental data of the powder-pack boronizing of Fe-15Cr alloy in the temperature range from 800 to 1050 °C and for a treatment time ranging from 0.5 to 12 h. The obtained results show that it is possible to estimate the influence of different process parameters. Comparing the results obtained by the artificial neural network to experimental data, the average error generated from the fuzzy neural network was 3% for the FeB layer and 3.5% for the Fe2B layer. The results obtained from the fuzzy neural network approach are in agreement with the experimental data. Finally, the utilization of fuzzy neural network approach is well adapted for the boronizing kinetics of Fe-15Cr alloy.

Use of Posterior Probabilities to Evaluate Methods of Discriminant Analysis

1981 ◽  
Vol 20 (04) ◽  
pp. 207-212 ◽  
Author(s):  
J. Hermans ◽  
B. van Zomeren ◽  
J. W. Raatgever ◽  
P. J. Sterk ◽  
J. D. F. Habbema
Keyword(s):  
Experimental Data ◽  
Discriminant Analysis ◽  
Posterior Probabilities

By means of a case study the choice between several methods of discriminant analysis is presented. Experimental data of a two-groups problem with one or two variables is analysed. The different methods are compared according to posterior probabilities which can be computed for each subject and which are the basis of discriminant analysis. These posterior probabilities are analysed graphically as well as numerically.

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