title: The role of connexin36 gap junctions in modulating the hypnotic effects of isoflurane and propofol in mice

authors: Jacobson, Gregory M.

subjects: Connexin36

abstract: Gap junction blockade is a possible mechanism by which general anaesthetic drugs cause unconsciousness. We measured the sensitivity of connexin36 knockout mice to the hypnotic effects of isoflurane and propofol. The experimental endpoint was recovery of the righting reflex of the anaesthetised animals during 0.2% step-reductions in isoflurane concentration, or following intraperitoneal injection of propofol (100 mg.kg⁻¹). Connexin36 knockout animals were more sensitive to the hypnotic effects of isoflurane than ‘normal’ wild-type animals. The half maximal effective concentration (EC50) for recovery of righting reflex was 0.37% for connexin36 knockout vs 0.49% for wild-type animals (p < 0.001). For propofol, connnexin36 knockout animals showed more rapid loss of righting reflex than wild-type animals (mean (SD) 2.8 (0.13) vs 3.8 (0.27) min); and young (< 60 days) connexin36 knockout animals remained anaesthetised for longer than young wild-type mice (47.2 (2.9) vs 30.5 (1.7) min; p < 0.00001). These findings suggest that the hypnotic effects of anaesthetic drugs may be moderately enhanced by gap junction blockade.

text: The role of connexin36 gap junctions in modulating the hypnotic effects of isoflurane and propofol in mice Gap junction blockade is a possible mechanism by which general anaesthetic drugs cause unconsciousness. We measured the sensitivity of connexin36 knockout mice to the hypnotic effects of isoflurane and propofol. The experimental endpoint was recovery of the righting reflex of the anaesthetised animals during 0.2% step-reductions in isoflurane concentration, or following intraperitoneal injection of propofol (100 mg.kg⁻¹). Connexin36 knockout animals were more sensitive to the hypnotic effects of isoflurane than ‘normal’ wild-type animals. The half maximal effective concentration (EC50) for recovery of righting reflex was 0.37% for connexin36 knockout vs 0.49% for wild-type animals (p < 0.001). For propofol, connnexin36 knockout animals showed more rapid loss of righting reflex than wild-type animals (mean (SD) 2.8 (0.13) vs 3.8 (0.27) min); and young (< 60 days) connexin36 knockout animals remained anaesthetised for longer than young wild-type mice (47.2 (2.9) vs 30.5 (1.7) min; p < 0.00001). These findings suggest that the hypnotic effects of anaesthetic drugs may be moderately enhanced by gap junction blockade.

year: 2011

title: Towards Meta-learning over Data Streams

authors: van Rijn, Jan N.

subjects: Machine learning

abstract: Modern society produces vast streams of data. Many stream mining algorithms have been developed to capture general trends in these streams, and make predictions for future observations, but relatively little is known about which algorithms perform particularly well on which kinds of data. Moreover, it is possible that the characteristics of the data change over time, and thus that a different algorithm should be recommended at various points in time. Figure 1 illustrates this. As such, we are dealing with the Algorithm Selection Problem [9] in a data stream setting. Based on measurable meta-features from a window of observations from a data stream, a meta-algorithm is built that predicts the best classifier for the next window. Our results show that this meta-algorithm is competitive with state-of-the art data streaming ensembles, such as OzaBag [6], OzaBoost [6] and Leveraged Bagging [3].

text: Towards Meta-learning over Data Streams Modern society produces vast streams of data. Many stream mining algorithms have been developed to capture general trends in these streams, and make predictions for future observations, but relatively little is known about which algorithms perform particularly well on which kinds of data. Moreover, it is possible that the characteristics of the data change over time, and thus that a different algorithm should be recommended at various points in time. Figure 1 illustrates this. As such, we are dealing with the Algorithm Selection Problem [9] in a data stream setting. Based on measurable meta-features from a window of observations from a data stream, a meta-algorithm is built that predicts the best classifier for the next window. Our results show that this meta-algorithm is competitive with state-of-the art data streaming ensembles, such as OzaBag [6], OzaBoost [6] and Leveraged Bagging [3].

year: 2014

title: Māori Goddesses in Literature Part 1: pre 1880 - 1900

authors: Yates-Smith, Aroha

subjects: Atua wāhine

abstract: Many contemporary Māori are familiar with atua wāhine, Māori goddesses, through accounts that have been passed on to them by word of mouth. Few, however, have had an opportunity to consult accounts of atua wāhine that date from the early period of Māori-Pākehā contact. Those who wish to do so may have considerable difficulty in sifting through all of the written materials for the information they seek. For this reason, this paper provides a review of the literature pertaining to atua wāhine from pre-1880 to 1900, together with a commentary on the sources to which reference is made. A review of literature on atua wāhine which appeared after 1900 will appear in the second volume of this journal.

text: Māori Goddesses in Literature Part 1: pre 1880 - 1900 Many contemporary Māori are familiar with atua wāhine, Māori goddesses, through accounts that have been passed on to them by word of mouth. Few, however, have had an opportunity to consult accounts of atua wāhine that date from the early period of Māori-Pākehā contact. Those who wish to do so may have considerable difficulty in sifting through all of the written materials for the information they seek. For this reason, this paper provides a review of the literature pertaining to atua wāhine from pre-1880 to 1900, together with a commentary on the sources to which reference is made. A review of literature on atua wāhine which appeared after 1900 will appear in the second volume of this journal.

year: 2000-10