title: Does bispectral analysis of the electroencephalogram add anything but complexity?

authors: Miller, A.

subjects: anaesthesia

abstract: Background: Analysis of the bispectrum of EEG waveforms is a component of the proprietary BIS index—a commonly used commercial monitor of depth of anaesthesia. Does the use of the bispectrum give more information about depth of anaesthesia than the power spectrum? Methods: We collected and analysed EEG waveforms during induction of general anaesthesia in 39 patients, comparing the changes in bispectral parameter (SynchFastSlow), with an analogous power spectrum-based parameter (PowerFastSlow). Both compare the logarithmic ratio of high frequency components (40–47 Hz) with the total (1–47 Hz). Because the changes in bispectrum are affected by signal amplitude, we also calculated a third parameter (SFSbicoh) from the bicoherence, which is an amplitude-independent statistic. Results: The SynchFastSlow and PowerFastSlow were correlated (r=0.84) and neither was superior in predicting the awake or anaesthetized state (area under receiver operating characteristic curves = 0.85 vs 0.93). There was no change in the SFSbicoh over the induction period, and it did not correlate with SynchFastSlow (r=0.07). Conclusions: We could not show that bispectral analysis gave more information than power spectral-based analysis. Most of the changes in the bispectral values result from decreases in the relative high frequency content of the EEG caused by anaesthesia.

text: Does bispectral analysis of the electroencephalogram add anything but complexity? Background: Analysis of the bispectrum of EEG waveforms is a component of the proprietary BIS index—a commonly used commercial monitor of depth of anaesthesia. Does the use of the bispectrum give more information about depth of anaesthesia than the power spectrum? Methods: We collected and analysed EEG waveforms during induction of general anaesthesia in 39 patients, comparing the changes in bispectral parameter (SynchFastSlow), with an analogous power spectrum-based parameter (PowerFastSlow). Both compare the logarithmic ratio of high frequency components (40–47 Hz) with the total (1–47 Hz). Because the changes in bispectrum are affected by signal amplitude, we also calculated a third parameter (SFSbicoh) from the bicoherence, which is an amplitude-independent statistic. Results: The SynchFastSlow and PowerFastSlow were correlated (r=0.84) and neither was superior in predicting the awake or anaesthetized state (area under receiver operating characteristic curves = 0.85 vs 0.93). There was no change in the SFSbicoh over the induction period, and it did not correlate with SynchFastSlow (r=0.07). Conclusions: We could not show that bispectral analysis gave more information than power spectral-based analysis. Most of the changes in the bispectral values result from decreases in the relative high frequency content of the EEG caused by anaesthesia.

year: 2004

title: Constructing a focused taxonomy from a document collection

authors: Medelyan, Olena

subjects: computer science

abstract: We describe a new method for constructing custom taxonomies from document collections. It involves identifying relevant concepts and entities in text; linking them to knowledge sources like Wikipedia, DBpedia, Freebase, and any supplied taxonomies from related domains; disambiguating conflicting concept mappings; and selecting semantic relations that best group them hierarchically. An RDF model supports interoperability of these steps, and also provides a flexible way of including existing NLP tools and further knowledge sources. From 2000 news articles we construct a custom taxonomy with 10,000 concepts and 12,700 relations, similar in structure to manually created counterparts. Evaluation by 15 human judges shows the precision to be 89% and 90% for concepts and relations respectively; recall was 75% with respect to a manually generated taxonomy for the same domain.

text: Constructing a focused taxonomy from a document collection We describe a new method for constructing custom taxonomies from document collections. It involves identifying relevant concepts and entities in text; linking them to knowledge sources like Wikipedia, DBpedia, Freebase, and any supplied taxonomies from related domains; disambiguating conflicting concept mappings; and selecting semantic relations that best group them hierarchically. An RDF model supports interoperability of these steps, and also provides a flexible way of including existing NLP tools and further knowledge sources. From 2000 news articles we construct a custom taxonomy with 10,000 concepts and 12,700 relations, similar in structure to manually created counterparts. Evaluation by 15 human judges shows the precision to be 89% and 90% for concepts and relations respectively; recall was 75% with respect to a manually generated taxonomy for the same domain.

year: 2013

title: Pinepine te Kura

authors: Maxwell, Te Kahautu

abstract: Whakaeke (entrance). Lyrics/Musical Score composed and choreographed by Te Kahautu Maxwell. Performed by Ōpōtiki Mai Tawhiti (Kapa Haka group) (3mins)

Waiata ā Tira: Aroha
Whakaeke: Pinepine Te Kura, Hau Te Kura
Mōteatea: Te Ao o Te Pārerā
Waiata ā Ringa: E pā to reo, Te Matatini, Herewini Parata
Poi: E ia e ia
Haka: Te Kōtiritiri, Te Kōtaratara
Whakawātea: Ōranga Tōiti, tōnui kōrero

text: Pinepine te Kura Whakaeke (entrance). Lyrics/Musical Score composed and choreographed by Te Kahautu Maxwell. Performed by Ōpōtiki Mai Tawhiti (Kapa Haka group) (3mins)

Waiata ā Tira: Aroha
Whakaeke: Pinepine Te Kura, Hau Te Kura
Mōteatea: Te Ao o Te Pārerā
Waiata ā Ringa: E pā to reo, Te Matatini, Herewini Parata
Poi: E ia e ia
Haka: Te Kōtiritiri, Te Kōtaratara
Whakawātea: Ōranga Tōiti, tōnui kōrero

year: 2023-02-22