Threshold vision under full-field stimulation: Revisiting the minimum number of quanta necessary to evoke a visual sensation

The receptive field (RF) of most retinal ganglion cells (RGCs) is comprised of an excitatory center and an antagonistic surround. Interactions between these RF elements shape most of the visual responses of RGCs. To begin to investigate center-surround interactions of mouse RGCs quantitatively, we characterized their responses in anin vivopreparation to a variety of spot and full-field stimuli. When RGCs were stimulated with a spot that matched the cell's RF center diameter (optimal spot), all RGCs could be categorized as either ON- or OFF-center. In all RGCs, full-field stimulation significantly reduced both the peak and the mean firing rates evoked with an optimal spot stimulus. Full-field stimulation revealed differences in other response properties between ON- and OFF-center RGCs. With a full-field stimulus, the duration of the OFF-center RGCs response was reduced making them more transient, while the duration of the ON-center RGCs increased making them more sustained. Of most interest, full-field stimulation altered the RF center response sign in approximately half of the OFF-center RGCs, which became either OFF/ON or ON only. In contrast, all ON-center and the other OFF-center cells conserved their RF response sign in the presence of the full-field stimulus. We propose that sign-altering OFF-center RGCs possess an additional RF surround mechanism that underlies this alteration in their response. Of general interest these results suggest that the sole use of full-field stimulation to categorize visual response properties of RGCs does not adequately reflect their RF organization and, therefore, is not an optimal strategy for their classification.

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P126 Full-field, hemi-field, and quadrant-field stimulation veps in patients with stroke without occipital lobe lesion

Clinical Neurophysiology ◽

10.1016/s1388-2457(08)60397-1 ◽

2008 ◽

Vol 119 ◽

pp. S103

Author(s):

Ferah Kizilay ◽

Hulya Aydin Gungor ◽

Berrin Aktekin ◽

Yesim Senol ◽

Sibel Ozkaynak

Keyword(s):

Occipital Lobe ◽

Field Stimulation ◽

Full Field

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Information capacity and bandwidth limitations in the SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152392 ◽

1989 ◽

Vol 47 ◽

pp. 84-85

Author(s):

D. C. Joy ◽

R. D. Bunn

Keyword(s):

Signal To Noise Ratio ◽

Critical Dimension ◽

Information Capacity ◽

Acquisition Time ◽

Signal To Noise ◽

Sem Image ◽

Probe Size ◽

Minimum Number ◽

Noise Ratio ◽

Signal Channel

The information available from an SEM image is limited both by the inherent signal to noise ratio that characterizes the image and as a result of the transformations that it may undergo as it is passed through the amplifying circuits of the instrument. In applications such as Critical Dimension Metrology it is necessary to be able to quantify these limitations in order to be able to assess the likely precision of any measurement made with the microscope.The information capacity of an SEM signal, defined as the minimum number of bits needed to encode the output signal, depends on the signal to noise ratio of the image - which in turn depends on the probe size and source brightness and acquisition time per pixel - and on the efficiency of the specimen in producing the signal that is being observed. A detailed analysis of the secondary electron case shows that the information capacity C (bits/pixel) of the SEM signal channel could be written as :

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Applying Generalizability Theory to Optimize Analysis of Spontaneous Teacher Talk in Elementary Classrooms

Journal of Speech Language and Hearing Research ◽

10.1044/2020_jslhr-19-00118 ◽

2020 ◽

Vol 63 (6) ◽

pp. 1947-1957

Author(s):

Alexandra Hollo ◽

Johanna L. Staubitz ◽

Jason C. Chow

Keyword(s):

Special Education Teachers ◽

Generalizability Theory ◽

Child Outcomes ◽

Elementary Classrooms ◽

Teacher Talk ◽

Group Instruction ◽

Data Set ◽

School Year ◽

Minimum Number ◽

Representative Samples

Purpose Although sampling teachers' child-directed speech in school settings is needed to understand the influence of linguistic input on child outcomes, empirical guidance for measurement procedures needed to obtain representative samples is lacking. To optimize resources needed to transcribe, code, and analyze classroom samples, this exploratory study assessed the minimum number and duration of samples needed for a reliable analysis of conventional and researcher-developed measures of teacher talk in elementary classrooms. Method This study applied fully crossed, Person (teacher) × Session (samples obtained on 3 separate occasions) generalizability studies to analyze an extant data set of three 10-min language samples provided by 28 general and special education teachers recorded during large-group instruction across the school year. Subsequently, a series of decision studies estimated of the number and duration of sessions needed to obtain the criterion g coefficient ( g > .70). Results The most stable variables were total number of words and mazes, requiring only a single 10-min sample, two 6-min samples, or three 3-min samples to reach criterion. No measured variables related to content or complexity were adequately stable regardless of number and duration of samples. Conclusions Generalizability studies confirmed that a large proportion of variance was attributable to individuals rather than the sampling occasion when analyzing the amount and fluency of spontaneous teacher talk. In general, conventionally reported outcomes were more stable than researcher-developed codes, which suggests some categories of teacher talk are more context dependent than others and thus require more intensive data collection to measure reliably.

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RGB Frequency Based Image Steganography

International Journal of Scientific Research in Computer Science Engineering and Information Technology ◽

10.32628/cseit206359 ◽

2020 ◽

pp. 549-553

Author(s):

Himanshu Kumar ◽

Nitesh Kumar

Keyword(s):

Image Steganography ◽

Minimum Number

In this paper, we introduced a new RGB technique for image steganography. In this technique we introduced the idea of storing a different number of bits per channel (R, G or B) of a pixel based on the frequency of color values of pixel. The higher color frequency retains the maximum number of bits and lower color frequency stores the minimum number of bits.

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On Number of Planes of Rearrangeably Nonblocking Optical Banyan Networks with Link Failures

Journal of Scientific Research ◽

10.3329/jsr.v1i1.1070 ◽

2008 ◽

Vol 1 (1) ◽

pp. 43-54

Author(s):

Basra Sultana ◽

Mamun-ur-Rashid Khandker

Keyword(s):

Optical Switching ◽

Blocking Probability ◽

Link Failure ◽

Link Failures ◽

Small Depth ◽

Internal Link ◽

Banyan Network ◽

Minimum Number ◽

Switch Design ◽

Banyan Networks

Vertically stacked optical banyan (VSOB) networks are attractive for serving as optical switching systems due to the desirable properties (such as the small depth and self-routing capability) of banyan network structures. Although banyan-type networks result in severe blocking and crosstalk, both these problems can be minimized by using sufficient number of banyan planes in the VSOB network structure. The number of banyan planes is minimum for rearrangeably nonblocking and maximum for strictly nonblocking structure. Both results are available for VSOB networks when there exist no internal link-failures. Since the issue of link-failure is unavoidable, we intend to find the minimum number of planes required to make a VSOB network nonblocking when some links are broken or failed in the structure. This paper presents the approximate number of planes required to make a VSOB networks rearrangeably nonblocking allowing link-failures. We also show an interesting behavior of theÂ blockingÂ probability of a faulty VSOB networks that the blocking probability may notÂ alwaysÂ increase monotonously withÂ theÂ increaseÂ ofÂ link-failures; blocking probabilityÂ decreasesÂ forÂ certain range ofÂ link-failures, and then increases again. We believe that such fluctuating behavior of blocking probability with the increase of link failure probability deserves special attention in switch design. Â Keywords: Banyan networks; Blocking probability; Switching networks; Vertical stacking; Link-failures.Â Â© 2009 JSR Publications. ISSN: 2070-0237(Print); 2070-0245 (Online). All rights reserved.Â DOI: 10.3329/jsr.v1i1.1070

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Full-Field Approach for Modeling of Microstructural Evolutions During Forming Processes

The 8th International SteelSim Conference ◽

10.33313/503/037 ◽

2019 ◽

Author(s):

S. Andrietti ◽

M. Bernacki ◽

N. Bozzolo ◽

L. Maire ◽

P. De Micheli ◽

...

Keyword(s):

Full Field ◽

Field Approach

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