A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessionngl94v96ndhmiqgv55920r1um9uj86sl): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Undefined array key "choices"

Filename: controllers/Detail.php

Line Number: 249

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 249

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 249

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 249

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: 8192

Message: strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated

Filename: models/Detail_model.php

Line Number: 71

Backtrace:

File: /var/www/html/application/models/Detail_model.php
Line: 71
Function: strpos

File: /var/www/html/application/controllers/Detail.php
Line: 252
Function: insertAPISummary

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: 8192

Message: str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated

Filename: helpers/my_audit_helper.php

Line Number: 8919

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 8919
Function: str_replace

File: /var/www/html/application/controllers/Detail.php
Line: 255
Function: formatAIDetailSummary

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Undefined array key "choices"

Filename: controllers/Detail.php

Line Number: 256

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 256

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 256

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Undefined array key "usage"

Filename: controllers/Detail.php

Line Number: 257

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 257
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 257

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 257
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Undefined array key "usage"

Filename: controllers/Detail.php

Line Number: 258

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 258
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 258

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 258
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Undefined array key "usage"

Filename: controllers/Detail.php

Line Number: 259

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 259
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 259

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 259
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Undefined array key "usage"

Filename: controllers/Detail.php

Line Number: 260

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 260
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 260

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 260
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Trying to access array offset on value of type null

Filename: controllers/Detail.php

Line Number: 260

Backtrace:

File: /var/www/html/application/controllers/Detail.php
Line: 260
Function: _error_handler

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests

Filename: helpers/my_audit_helper.php

Line Number: 143

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3098
Function: getPubMedXML

File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Attempt to read property "Count" on bool

Filename: helpers/my_audit_helper.php

Line Number: 3100

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3100
Function: _error_handler

File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

Brain electrical activity obeys Benford's law. | LitMetric

Brain electrical activity obeys Benford's law.

Anesth Analg

From the *Department of Anesthesiology, Klinikum rechts der Isar, Technische Universität München, München; †Department of Anesthesiology, Experimental Anesthesiology Section, University of Tübingen, Tübingen; and ‡Department of Anesthesiology, Witten/Herdecke University, Helios Clinic Wuppertal, Germany.

Published: January 2014

AI Article Synopsis

Article Abstract

Background: Monitoring and automated online analysis of brain electrical activity are frequently used for verifying brain diseases and for estimating anesthetic depth in subjects undergoing surgery. However, false diagnosis with potentially catastrophic consequences for patients such as intraoperative awareness may result from unnoticed irregularities in the process of signal analysis. Here we ask whether Benford's Law can be applied to detect accidental or intended modulation of neurophysiologic signals. This law states that the first digits of many datasets such as atomic weights or river lengths are distributed logarithmically and not equally. In particular, we tested whether data obtained from electrophysiological recordings of human patients representing global activity and organotypic slice cultures representing pure cortical activity follow the predictions of Benford's Law in the absence and in the presence of an anesthetic drug.

Methods: Electroencephalographic (EEG) recordings from human subjects and local field potential recordings from cultured cortical brain slices were obtained before and after administration of sevoflurane. The first digit distribution of the datasets was compared with the Benford distribution.

Results: All datasets showed a Benford-like distribution. Nevertheless, distributions belonging to different anesthetic levels could be distinguished in vitro and in human EEGs. With sevoflurane, the first digit distribution of the in vitro data becomes steeper, while it flattens for EEG data. In the presence of high frequency noise, the Benford distribution falls apart.

Conclusions: In vitro and EEG data show a Benford-like distribution which is altered by sevoflurane or destroyed by noise used to simulate artefacts. These findings suggest that algorithms based on Benford's Law can be successfully used to detect sevoflurane-induced signal modulations in electrophysiological recordings.

Download full-text PDF

Source
http://dx.doi.org/10.1213/ANE.0000000000000015DOI Listing

Publication Analysis

Top Keywords

benford's law
16
brain electrical
8
electrical activity
8
electrophysiological recordings
8
recordings human
8
sevoflurane digit
8
digit distribution
8
benford-like distribution
8
eeg data
8
law
5

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!