Integrated mismatch negativity (MMNi): a noise-free representation of evoked responses allowing single-point distribution-free statistical tests

Author(s):  
Curtis W Ponton ◽  
Manuel Don ◽  
Jos J Eggermont ◽  
Betty Kwong
Sensors ◽  
2019 ◽  
Vol 19 (9) ◽  
pp. 2137 ◽  
Author(s):  
Soojeong Lee ◽  
Gangseong Lee ◽  
Gwanggil Jeon

Oscillometric blood pressure (BP) monitors currently estimate a single point but do not identify variations in response to physiological characteristics. In this paper, to analyze BP’s normality based on oscillometric measurements, we use statistical approaches including kurtosis, skewness, Kolmogorov-Smirnov, and correlation tests. Then, to mitigate uncertainties, we use a deep learning method to determine the confidence limits (CLs) of BP measurements based on their normality. The proposed deep learning regression model decreases the standard deviation of error (SDE) of the mean error and the mean absolute error and reduces the uncertainties of the CLs and SDEs of the proposed technique. We validate the normality of the distribution of the BP estimation which fits the standard normal distribution very well. We use a rank test in the deep learning technique to demonstrate the independence of the artificial systolic BP and diastolic BP estimations. We perform statistical tests to verify the normality of the BP measurements for individual subjects. The proposed methodology provides accurate BP estimations and reduces the uncertainties associated with the CLs and SDEs using the deep learning algorithm.


F1000Research ◽  
2013 ◽  
Vol 2 ◽  
pp. 182
Author(s):  
Kestutis Gurevicius ◽  
Arto Lipponen ◽  
Rimante Minkeviciene ◽  
Heikki Tanila

An auditory oddball paradigm in humans generates a long-duration cortical negative potential, often referred to as mismatch negativity. Similar negativity has been documented in monkeys and cats, but it is controversial whether mismatch negativity also exists in awake rodents. To this end, we recorded cortical and hippocampal evoked responses in rats during alert immobility under a typical passive oddball paradigm that yields mismatch negativity in humans. The standard stimulus was a 9 kHz tone and the deviant either 7 or 11 kHz tone in the first condition. We found no evidence of a sustained potential shift when comparing evoked responses to standard and deviant stimuli. Instead, we found repetition-induced attenuation of the P60 component of the combined evoked response in the cortex, but not in the hippocampus. The attenuation extended over three days of recording and disappeared after 20 intervening days of rest. Reversal of the standard and deviant tones resulted is a robust enhancement of the N40 component not only in the cortex but also in the hippocampus. Responses to standard and deviant stimuli were affected similarly. Finally, we tested the effect of scopolamine in this paradigm. Scopolamine attenuated cortical N40 and P60 as well as hippocampal P60 components, but had no specific effect on the deviant response. We conclude that in an oddball paradigm the rat demonstrates repetition-induced attenuation of mid-latency responses, which resembles attenuation of the N1-component of human auditory evoked potential, but no mismatch negativity.


2020 ◽  
Vol 6 (1) ◽  
pp. 11-21
Author(s):  
Gleb A. Akilin ◽  
Vladimir А. Fedorov ◽  
Evgeny V. Gritskevich ◽  
Polina A. Zviagintseva

Simulation computer model of an optoelectronic coordinate measurer for point objects is considered that is a part of the subject recognition system based on biometric features. The presented model allows you to virtually explore and analyze the processes of functioning of the coordinator, which ensures optimal coordination of parameters and characteristics of various parts of the device, as well as to choose the most effective algorithm for processing the resulting digital image by minimizing the error of measuring the coordinates of a single point object. The simulation is based on the Monte Carlo method of multiple statistical tests, which provides most accurate representation of noise processes that occur when receiving and converting optical information in the optical-electronic path of a coordinate device, since these processes, under solid equal conditions, make a decisive contribution to the final measurement error. The principles of the model are described and the results obtained are discussed, as well as the future development of the model and its application for solving problems of optimal system design of biometric recognition systems.


2021 ◽  
Author(s):  
Nadežda Stojanov ◽  
Tijana Zeremski ◽  
Snežana Maletić ◽  
Milorad Živanov ◽  
Jelena Tričković

<p>Biochar is promising material used to enhance organic matter content in soil and to mitigate climate change through carbon sequestration. In addition to that, biochar increases crop yield by means of improving soil capacity for water- and nutrient-holding capacity, and due to its adsorption capacity, it decreases mobility and bioavailability of organic pollutants and heavy metals. Biochar (BC) is a carbon-rich and porous material produced by pyrolysis of biomass under oxygen-limited conditions. The unwanted spread of pesticides to the environment and their leaching into the groundwater is of great concern. The aim of this work is to investigate the potential of BC to improve the adsorption capacity for two triazine herbicides in three different soil types with various organic matter (OC) content. Triazine herbicides (terbuthylazine and atrazine) were chosen as the most widely used pesticides in recent decades. The main difference among between three different soils types used in the study is in their OM content, which was 0.48%, 2.34% and 4.12%, respectively for Soil1, Soil2, and Soil3. The BC used in this work is commercially available compost-activated biochar produced by pyrolysis of beechwood chips at 700 <sup>o</sup>C. A batch adsorption experiments were conducted to investigate herbicide adsorption in soil without BC and with the amendment of BC (0, 1, 5, and 10%). The concentration of herbicides in the aqueous phase at equilibrium (which is achieved after 72 h) was determined by GC-MS. The adsorption isotherms were well described with the Freundlich model (R<sup>2</sup> values range from 0.714 to 0.998). Values of Freundlich exponent <em>n</em> were less than 1 (from 0.314 to 0.897), which indicates that the isotherms are of L-type. This shows that with the increase of compound concentration relative adsorption decreases because of the saturation of adsorption sites. Single-point distribution coefficients (<em>K<sub>d</sub></em>) were calculated at selected equilibrium concentration (<em>c<sub>e</sub></em>= 100 µg dm<sup>–3</sup>). <em>K<sub>d</sub></em> values increased with an increase of BC content, especially for 5% and 10% of BC amendment. <em>K<sub>d</sub></em> values of atrazine in Soil1 were in the range 1.91–14.55, in Soil2 from 4.76–15.65, and in Soil3 from 4.79–20.11, while <em>K<sub>d</sub></em> values of terbuthylazine ranged from 1.14–30.92 in Soil1, from 14.13–50.74 in Soil2, and from 12.65–47.03 in Soil3. In unamended Soil1 the adsorption of both herbicides was lower in comparison to unamended Soil2 and Soil3, which is in accordance with the well-known fact that the OC content of soil primarily affects the adsorption of pesticides. The adsorption capacity of Soil 2 and Soil 3 was not significantly different. It is observed that the adsorption of terbuthylazine is higher in all soil types, which is in accordance with its lower solubility and higher affinity for OM in comparison to atrazine. It is shown that sorption capacity of soil for pesticides could be improved by adding biochar into the soil, thus reducing herbicide mobility into the environment. Further studies will be conducted by column experiments to investigate more realistic environmental scenarios.</p>


1978 ◽  
Vol 46 (3_suppl) ◽  
pp. 1023-1032 ◽  
Author(s):  
Maryellen McSweeney ◽  
Barry M. Katz

This paper clarifies the distinctions among parametric, non-parametric, and distribution free statistical tests. The principal circumstances prompting the use of nonparametric procedures, both rank order and qualitative data Techniques, are identified and illustrated. Historical factors and disciplinary orientations affecting the use of nonparametric procedures are discussed. Finally, some conditions which are conducive to the more frequent use of nonparametric statistics are identified.


Technometrics ◽  
1970 ◽  
Vol 12 (4) ◽  
pp. 929-929
Author(s):  
C. B. Bell

2018 ◽  
Vol 18 (5) ◽  
pp. 77-86 ◽  
Author(s):  
Dmitry Osipov ◽  
Dmitry Titov

Abstract The following paper adapts the classical Zigangirov-Jelinek algorithm to the decoding of nonbinary block codes under severe mixed jamming. To ensure reliable communications in this scenario we combine reception techniques based on distribution free statistical tests with sequential decoding on syndrome trellises. It will be shown that the proposed approach can ensure relatively high transmission rate with reasonable complexity.


Author(s):  
Soojeong Lee ◽  
Joon-Hyuk Chang

Oscillometric blood pressure (BP) devices currently estimate a single point but do not identify fluctuations in BP or distinguish them from variations in response to physiological properties. In this paper, to analyze BP normality based on oscillometric measurements, we use statistical approaches including kurtosis, skewness, Kolmogorov-Smirnov, and correlation tests. Then, to mitigate uncertainties, we use a deep neural network (DNN) to determine the confidence limits (CLs) of BP measurements based on their normality. The proposed DNN regression model decreases the standard deviation of error (SDE) of the mean error (ME) and the mean absolute error (MAE) and reduces the uncertainty of the CLs and SDEs of the proposed technique. We validate the normality of the distribution of the BP estimation distribution which fits the Gaussian distribution very well. We use a rank test in the DNN regression model to demonstrate the independence of the artificial SBP and DBP estimations. First, we perform statistical tests to verify the normality of the BP measurements for individual subjects. The proposed methodology provides accurate BP estimations and reduces the uncertainties associated with the CLs and SDEs based on the DNN regression estimator.


1969 ◽  
Vol 10 (2) ◽  
pp. 150-151
Author(s):  
H. L. Janzen

2017 ◽  
pp. 262-276
Author(s):  
Riitta Hari ◽  
Aina Puce

This chapter discusses, in the context of the predictive-coding framework, evoked responses to various changes in the environment and describes how the responses are related to variations in stimulus probability and the subject’s expectations. The focus is on three well-known responses: (a) the mismatch negativity peaking at 100 to 250 ms and elicited to changes in stimulus attributes, even when the stimuli are not attended to, (b) the P300 response peaking about 300 ms after attended low-probability “oddball” stimuli, and (c) the N400 peaking about 400 ms after semantic or lexical violations of sentences presented either visually or auditorily. Continent negative variation and error-related negativity are introduced as well.


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