title: The Global Stratotype Section and Point (GSSP) for the base of the Holocene Series/Epoch (Quaternary System/Period) in the NGRIP ice core

authors: Walker, Mike

subjects: Geoscience

abstract: The Greenland ice core from NorthGRIP (NGRIP) contains a proxy climate record across the Pleistocene– Holocene boundary of unprecedented clarity and resolution. Analysis of an array of physical and chemical parameters within the ice enables the base of the Holocene, as reflected in the first signs of climatic warming at the end of the Younger Dryas/Greenland Stadial 1 cold phase, to be located with a high degree of precision. This climatic event is most clearly reflected in an abrupt shift in deuterium excess values, accompanied by more gradual changes in d18O, dust concentration, a range of chemical species, and annual layer thickness. A timescale based on multi-parameter annual layer counting provides an age of 11,700 yr b2k (before AD2000) for the base of the Holocene, with an estimated 2s uncertainty of 99 yr. It is proposed that an archived core from this unique sequence should constitute the Global Stratotype Section and Point (GSSP) for the base of the Holocene Series/Epoch (Quaternary System/Period).

text: The Global Stratotype Section and Point (GSSP) for the base of the Holocene Series/Epoch (Quaternary System/Period) in the NGRIP ice core The Greenland ice core from NorthGRIP (NGRIP) contains a proxy climate record across the Pleistocene– Holocene boundary of unprecedented clarity and resolution. Analysis of an array of physical and chemical parameters within the ice enables the base of the Holocene, as reflected in the first signs of climatic warming at the end of the Younger Dryas/Greenland Stadial 1 cold phase, to be located with a high degree of precision. This climatic event is most clearly reflected in an abrupt shift in deuterium excess values, accompanied by more gradual changes in d18O, dust concentration, a range of chemical species, and annual layer thickness. A timescale based on multi-parameter annual layer counting provides an age of 11,700 yr b2k (before AD2000) for the base of the Holocene, with an estimated 2s uncertainty of 99 yr. It is proposed that an archived core from this unique sequence should constitute the Global Stratotype Section and Point (GSSP) for the base of the Holocene Series/Epoch (Quaternary System/Period).

year: 2008-06

title: Enhanced sample preparation for quantitation of microcystins by matrix-assisted laser desorption/ionisation–time of flight mass spectrometry

authors: Puddick, Jonathan

subjects: MALDI–TOF mass spectrometry

abstract: Introduction: Microcystins (MCs) are a group of cyanotoxins which pose a serious health threat when present in aquatic systems. Quantitative analysis of MCs by matrix-assisted laser desorption/ionisation–time of flight (MALDI–TOF) mass spectrometry has potential for the processing of large numbers of samples quickly and economically. The existing method uses an expensive internal standard and protocols that are incompatible with automated sample preparation and data acquisition.
Objective: To produce a MALDI–TOF sample preparation technique for the quantitation of MCs that not only maintains reproducibility and sensitivity, but is also compatible with an automated work-flow.
Methodology: Seven different MALDI–TOF sample preparations were assessed for signal reproducibility (coefficient of variation) and sensitivity (method detection limit) using a cost-effective internal standard (angiotensin I). The best preparation was then assessed for its quantitative performance using three different MC congeners ([Dha7] MC-LR, MC-RR and MC-YR).
Results: The sensitivity of six of the preparations was acceptable, as was the reproducibility for two thin-layer preparations performed on a polished steel target. Both thin-layer preparations could be used with a MALDI-TOF mass spectrometer that automatically acquires data, and one could be used in an automated sample preparation work-flow. Further investigation using the thin-layer spot preparation demonstrated that linear quantification of three different MC congeners was possible.
Conclusion: The study demonstrates that with different sample preparation methods and modern instrumentation, large numbers of samples can be analysed rapidly for MCs at low cost.

text: Enhanced sample preparation for quantitation of microcystins by matrix-assisted laser desorption/ionisation–time of flight mass spectrometry Introduction: Microcystins (MCs) are a group of cyanotoxins which pose a serious health threat when present in aquatic systems. Quantitative analysis of MCs by matrix-assisted laser desorption/ionisation–time of flight (MALDI–TOF) mass spectrometry has potential for the processing of large numbers of samples quickly and economically. The existing method uses an expensive internal standard and protocols that are incompatible with automated sample preparation and data acquisition.
Objective: To produce a MALDI–TOF sample preparation technique for the quantitation of MCs that not only maintains reproducibility and sensitivity, but is also compatible with an automated work-flow.
Methodology: Seven different MALDI–TOF sample preparations were assessed for signal reproducibility (coefficient of variation) and sensitivity (method detection limit) using a cost-effective internal standard (angiotensin I). The best preparation was then assessed for its quantitative performance using three different MC congeners ([Dha7] MC-LR, MC-RR and MC-YR).
Results: The sensitivity of six of the preparations was acceptable, as was the reproducibility for two thin-layer preparations performed on a polished steel target. Both thin-layer preparations could be used with a MALDI-TOF mass spectrometer that automatically acquires data, and one could be used in an automated sample preparation work-flow. Further investigation using the thin-layer spot preparation demonstrated that linear quantification of three different MC congeners was possible.
Conclusion: The study demonstrates that with different sample preparation methods and modern instrumentation, large numbers of samples can be analysed rapidly for MCs at low cost.

year: 2011

title: Ko ētehi waiata tangi o Pare Hauraki

authors: Ngāpō, Korohere

subjects: Waiata tangi

abstract: Inā hiahia ai te tangata kia mōhio ngā momo mōteatea o Pare Hauraki i ngā wā o mua me huri atu rātou ki ngā wāhi kohinga waiata pērā i Ngā Mōteatea a Ngata. Ka mutu kua tuhia tēnei pitopito kōrero hei tautoko atu i te hui waiata tawhito i whakatūria i Te Whare Wānanga o Waikato i te 2008. He tirohanga tēnei tuhinga ki te momo o ngā waiata e rua kāore i āta waiatahia, i āta rangona i runga i ngā marae o Hauraki ā mohoa nei. Ka mutu mā te waihape atu anō ki tētehi waiata i titoa e Pua ki Tawhiti mō tōna tungāne tae noa atu ki te waiata tangi i titoa e Wetea rāua ko Tūkehu, tēnā pea, ka ara ake anō te whakaaro me hoki anō ngā iwi o Pare Hauraki ki te waiata atu anō i ēnei waiata.

text: Ko ētehi waiata tangi o Pare Hauraki Inā hiahia ai te tangata kia mōhio ngā momo mōteatea o Pare Hauraki i ngā wā o mua me huri atu rātou ki ngā wāhi kohinga waiata pērā i Ngā Mōteatea a Ngata. Ka mutu kua tuhia tēnei pitopito kōrero hei tautoko atu i te hui waiata tawhito i whakatūria i Te Whare Wānanga o Waikato i te 2008. He tirohanga tēnei tuhinga ki te momo o ngā waiata e rua kāore i āta waiatahia, i āta rangona i runga i ngā marae o Hauraki ā mohoa nei. Ka mutu mā te waihape atu anō ki tētehi waiata i titoa e Pua ki Tawhiti mō tōna tungāne tae noa atu ki te waiata tangi i titoa e Wetea rāua ko Tūkehu, tēnā pea, ka ara ake anō te whakaaro me hoki anō ngā iwi o Pare Hauraki ki te waiata atu anō i ēnei waiata.

year: 2011