title: Mass Spectral Characterisation of Three New Groups  of Algal Toxins

authors: Knudsen, Brent Kevin

subjects: pectenotoxin

abstract: This thesis reports the mass spectral identification and characterisation of three new groups of algal compounds.

A series of novel pectenotoxins (PTXs) were identified in retained sub-samples of Irish mussel extracts that had previously been utilised to obtain bulk quantities of some other algal toxins. The first eluting of the novel pectenotoxins, when analysed on a C-18 column using an MeCN-H2O gradient, afforded MNH4+ and MNa+ ions at m/z 864 and 869 respectively. This compound was designated as PTX-i. Three minor isomers (possibly storage artefacts) of the dominant PTX-i compound were also detected in the retained extracts, together with several later eluting sulfonated and sulfonated fatty acid ester analogues of PTX-i. The dominant fatty acid analogues were found to be the 16:0 esters. Sulfonated PTX-i isomers and their 16:0 fatty acid ester analogues showed strong m/z 925 and 1163 ion responses respectively in negative ion mode. High resolution mass spectrometry (HRMS) data showed the atomic composition of the m/z 925 ion to be C47H69O17S. Full scan, MS2, MS3 and MS4 mass spectral data determined in both positive and negative ion modes for the three series of PTX-i compounds was consistent with the proposal that they possessed a C5H11O3 side chain attached to C-35, rather than a 36-hemiacetal ring system as found in other known pectenotoxins, and that the sulfate and fatty acid residues were attached to two of the hydroxyl groups believed to present in the C5H11O3 side chain.

An algal water sample collected from Vigo, Spain (Dinophysis acuta, 12/12/05), that had previously been extracted with CH2Cl2 and Et2O, was found to contain low levels of two new pectenotoxin-2 seco acid (PTX-2SA) analogues that showed MNH4+ and MNa+ ions at m/z 896 and 901 respectively. Full scan, MS2, MS3 and MS4 mass spectral data determined in positive ion mode, in combination with NaBH4 and NaBD4 reduction reaction product data determined for PTX-2SA and the two new compounds, established that the new compounds were 14-hydroxy analogues of PTX-2SA.
The Spanish algal water sample also found to contain an appreciable level of two glycosides which were identified from a combination of full scan, MS2, MS3 and MS4 mass spectral data determined in both positive and negative ion modes as either 7- or 24-O-glycosides of okadaic acid (OA) and dinophysistoxin-2 (DTX-2), as MSn data excluded C-2 or C-27 O-glycosylation. 1D and 2D-1H NMR, obtained by co-workers while the mass spectral investigations reported in this thesis were in progress, showed that the glycosides were the 24-β-O-glucopyranosyl analogues of OA and DTX-2.

A set of three New Zealand derived algal water extracts, two from West Coast, South Island (Dinophysis acuta) and one from Akaroa Harbour (Dinophysis acuminata), were prepared and analysed for the three groups of new algal compounds reported in this thesis. PTX-i and its analogues were not detected in any of the New Zealand samples, the two 14-hydroxy PTX-2SA compounds were detected in one of the West Coast samples and the Akaroa Harbour samples and 24-O-glucoside OA and DTX-2 analogues were only detected in the Akaroa Harbour sample.

text: Mass Spectral Characterisation of Three New Groups  of Algal Toxins This thesis reports the mass spectral identification and characterisation of three new groups of algal compounds.

A series of novel pectenotoxins (PTXs) were identified in retained sub-samples of Irish mussel extracts that had previously been utilised to obtain bulk quantities of some other algal toxins. The first eluting of the novel pectenotoxins, when analysed on a C-18 column using an MeCN-H2O gradient, afforded MNH4+ and MNa+ ions at m/z 864 and 869 respectively. This compound was designated as PTX-i. Three minor isomers (possibly storage artefacts) of the dominant PTX-i compound were also detected in the retained extracts, together with several later eluting sulfonated and sulfonated fatty acid ester analogues of PTX-i. The dominant fatty acid analogues were found to be the 16:0 esters. Sulfonated PTX-i isomers and their 16:0 fatty acid ester analogues showed strong m/z 925 and 1163 ion responses respectively in negative ion mode. High resolution mass spectrometry (HRMS) data showed the atomic composition of the m/z 925 ion to be C47H69O17S. Full scan, MS2, MS3 and MS4 mass spectral data determined in both positive and negative ion modes for the three series of PTX-i compounds was consistent with the proposal that they possessed a C5H11O3 side chain attached to C-35, rather than a 36-hemiacetal ring system as found in other known pectenotoxins, and that the sulfate and fatty acid residues were attached to two of the hydroxyl groups believed to present in the C5H11O3 side chain.

An algal water sample collected from Vigo, Spain (Dinophysis acuta, 12/12/05), that had previously been extracted with CH2Cl2 and Et2O, was found to contain low levels of two new pectenotoxin-2 seco acid (PTX-2SA) analogues that showed MNH4+ and MNa+ ions at m/z 896 and 901 respectively. Full scan, MS2, MS3 and MS4 mass spectral data determined in positive ion mode, in combination with NaBH4 and NaBD4 reduction reaction product data determined for PTX-2SA and the two new compounds, established that the new compounds were 14-hydroxy analogues of PTX-2SA.
The Spanish algal water sample also found to contain an appreciable level of two glycosides which were identified from a combination of full scan, MS2, MS3 and MS4 mass spectral data determined in both positive and negative ion modes as either 7- or 24-O-glycosides of okadaic acid (OA) and dinophysistoxin-2 (DTX-2), as MSn data excluded C-2 or C-27 O-glycosylation. 1D and 2D-1H NMR, obtained by co-workers while the mass spectral investigations reported in this thesis were in progress, showed that the glycosides were the 24-β-O-glucopyranosyl analogues of OA and DTX-2.

A set of three New Zealand derived algal water extracts, two from West Coast, South Island (Dinophysis acuta) and one from Akaroa Harbour (Dinophysis acuminata), were prepared and analysed for the three groups of new algal compounds reported in this thesis. PTX-i and its analogues were not detected in any of the New Zealand samples, the two 14-hydroxy PTX-2SA compounds were detected in one of the West Coast samples and the Akaroa Harbour samples and 24-O-glucoside OA and DTX-2 analogues were only detected in the Akaroa Harbour sample.

year: 2009

title: Trends and gaps

authors: Dix, Alan

subjects: Computer science

abstract: This chapter attempts to identify future research directions for formal methods in HCI. It does this using two main approaches. First, we will look at trends within HCI more broadly and the challenges these pose for formal methods. These trends in HCI are often themselves driven by external technical and societal change, for example the growth of maker/hacker culture and the increasing dependence of basic citizenship on digital technology, effectively establishing external requirements for the field. Second we will look inwards at the FoMHCI literature, the user interaction phenomena it is trying to address and the processes of interaction design it is intended to support. Through this second analysis we will identify internally generated trends. This does not lead to a single overarching research agenda, but does identify a number of critical areas and issues, and hence establishes opportunities for further research to expand the state of the art.

text: Trends and gaps This chapter attempts to identify future research directions for formal methods in HCI. It does this using two main approaches. First, we will look at trends within HCI more broadly and the challenges these pose for formal methods. These trends in HCI are often themselves driven by external technical and societal change, for example the growth of maker/hacker culture and the increasing dependence of basic citizenship on digital technology, effectively establishing external requirements for the field. Second we will look inwards at the FoMHCI literature, the user interaction phenomena it is trying to address and the processes of interaction design it is intended to support. Through this second analysis we will identify internally generated trends. This does not lead to a single overarching research agenda, but does identify a number of critical areas and issues, and hence establishes opportunities for further research to expand the state of the art.

year: 2017

title: The Daldy Mcwilliams ‘Outrage’ of 1879

authors: Hart, Philip

abstract: In the later 1870s, conflicts developed near Paeroa between a small hapu, Ngati Hako, and other hapu over land sales and surveys. In 1879, after some members of Ngati Koi offered to sell the Pukehanga Block, at Rotokohu, between Paeroa and Te Aroha, to the Crown, surveyors were sent to determine the boundaries despite threats of violence from Ngati Hako. These threats became a reality with shots being fired, wounding a surveyor’s assistant, ‘Daldy’ McWilliams, who survived by playing dead. Despite Pakeha fury about a ‘weak’ response, officials reacted cautiously, fearing to provoke a wider conflict. 
Instead of trying to arrest the two men accused of the attempted murder, which would have been difficult, because Ngati Hako claimed their action was justified the Native Minister encouraged senior Hauraki rangatira to convene a rununga to examine their claim. Ngati Hako said that the block of land was theirs, and as previously other land had been surveyed without their permission they had taken this action. The government was criticized for paying advances on a block that had not been through the land court, and the rununga determined that although Ngati Hako had acted wrongfully, their action could be justified. When Ngati Hako refused to hand over the two accused to the authorities, the rununga claimed not to have the power to hand them over; Ngati Hako then constructed two pa to defend themselves.
Such actions provoked much frustration and criticisms of the government amongst Pakeha, but officials who investigated Ngati Hako’s complaints agreed that they had indeed lost land unjustly. Once the owners of a large domain, they had lost their land to the invading Marutuahu, whose slaves they became. When the two accused were arrested in 1882 one was found not guilty and the other was amnestied after eight months in prison because it was believed that, as rangatira, they probably had not fired the shots but had taken the responsibility for the actions of their hapu. As for McWilliams, he received what he considered inadequate compensation.
This ‘outrage’ was the first and only time in Hauraki that a Maori had shot a Pakeha, and the government’s cautious but firm response meant that the ‘peace of Hauraki’, although disturbed for a while, was maintained.

text: The Daldy Mcwilliams ‘Outrage’ of 1879 In the later 1870s, conflicts developed near Paeroa between a small hapu, Ngati Hako, and other hapu over land sales and surveys. In 1879, after some members of Ngati Koi offered to sell the Pukehanga Block, at Rotokohu, between Paeroa and Te Aroha, to the Crown, surveyors were sent to determine the boundaries despite threats of violence from Ngati Hako. These threats became a reality with shots being fired, wounding a surveyor’s assistant, ‘Daldy’ McWilliams, who survived by playing dead. Despite Pakeha fury about a ‘weak’ response, officials reacted cautiously, fearing to provoke a wider conflict. 
Instead of trying to arrest the two men accused of the attempted murder, which would have been difficult, because Ngati Hako claimed their action was justified the Native Minister encouraged senior Hauraki rangatira to convene a rununga to examine their claim. Ngati Hako said that the block of land was theirs, and as previously other land had been surveyed without their permission they had taken this action. The government was criticized for paying advances on a block that had not been through the land court, and the rununga determined that although Ngati Hako had acted wrongfully, their action could be justified. When Ngati Hako refused to hand over the two accused to the authorities, the rununga claimed not to have the power to hand them over; Ngati Hako then constructed two pa to defend themselves.
Such actions provoked much frustration and criticisms of the government amongst Pakeha, but officials who investigated Ngati Hako’s complaints agreed that they had indeed lost land unjustly. Once the owners of a large domain, they had lost their land to the invading Marutuahu, whose slaves they became. When the two accused were arrested in 1882 one was found not guilty and the other was amnestied after eight months in prison because it was believed that, as rangatira, they probably had not fired the shots but had taken the responsibility for the actions of their hapu. As for McWilliams, he received what he considered inadequate compensation.
This ‘outrage’ was the first and only time in Hauraki that a Maori had shot a Pakeha, and the government’s cautious but firm response meant that the ‘peace of Hauraki’, although disturbed for a while, was maintained.

year: 2016