title: Reduced magnetohydrodynamics and parallel spectral transfer

authors: Oughton, Sean

subjects: mathematics

abstract: The self-consistency of the reduced magnetohydrodynamics (RMHD) model is explored by examining whether (parallel) spectral transfer might invalidate the assumptions employed in deriving it. Using direct numerical simulations we find that transfer of energy to structures with high parallel wavenumber is in fact limited by ongoing perpendicular transfer. Thus, the dynamics associated with RMHD models remains consistent with the underlying assumptions of RMHD. In particular, in well-resolved simulations it is neither necessary nor correct to introduce additional dissipation terms that (artificially) damp spectral transfer parallel to the mean magnetic field B0.

text: Reduced magnetohydrodynamics and parallel spectral transfer The self-consistency of the reduced magnetohydrodynamics (RMHD) model is explored by examining whether (parallel) spectral transfer might invalidate the assumptions employed in deriving it. Using direct numerical simulations we find that transfer of energy to structures with high parallel wavenumber is in fact limited by ongoing perpendicular transfer. Thus, the dynamics associated with RMHD models remains consistent with the underlying assumptions of RMHD. In particular, in well-resolved simulations it is neither necessary nor correct to introduce additional dissipation terms that (artificially) damp spectral transfer parallel to the mean magnetic field B0.

year: 2004-04-16

title: An expert-driven framework for applying eDNA tools to improve biosecurity in the Antarctic

authors: Clarke, Laurence J.

abstract: Signatories to the Antarctic Treaty System’s Environmental Protocol are committed to preventing incursions of non-native species into Antarctica, but systematic surveillance is rare. Environmental DNA (eDNA) methods provide new opportunities for enhancing detection of non-native species and biosecurity monitoring. To be effective for Antarctic biosecurity, eDNA tests must have appropriate sensitivity and specificity to distinguish non-native from native Antarctic species, and be fit-for-purpose. This requires knowledge of the priority risk species or taxonomic groups for which eDNA surveillance will be informative, validated eDNA assays for those species or groups, and reference DNA sequences for both target non-native and related native Antarctic species. Here, we used an expert elicitation process and decision-by-consensus approach to identify and assess priority biosecurity risks for the Australian Antarctic Program (AAP) in East Antarctica, including identifying high priority non-native species and their potential transport pathways. We determined that the priority targets for biosecurity monitoring were not individual species, but rather broader taxonomic groups such as mussels (Mytilus species), tunicates (Ascidiacea), springtails (Collembola), and grasses (Poaceae). These groups each include multiple species with high risks of introduction to and/or establishment in Antarctica. The most appropriate eDNA methods for the AAP must be capable of detecting a range of species within these high-risk groups (e.g., eDNA metabarcoding). We conclude that the most beneficial Antarctic eDNA biosecurity applications include surveillance of marine species in nearshore environments, terrestrial invertebrates, and biofouling species on vessels visiting Antarctica. An urgent need exists to identify suitable genetic markers for detecting priority species groups, establish baseline terrestrial and marine biodiversity for Antarctic stations, and develop eDNA sampling methods for detecting biofouling organisms.

text: An expert-driven framework for applying eDNA tools to improve biosecurity in the Antarctic Signatories to the Antarctic Treaty System’s Environmental Protocol are committed to preventing incursions of non-native species into Antarctica, but systematic surveillance is rare. Environmental DNA (eDNA) methods provide new opportunities for enhancing detection of non-native species and biosecurity monitoring. To be effective for Antarctic biosecurity, eDNA tests must have appropriate sensitivity and specificity to distinguish non-native from native Antarctic species, and be fit-for-purpose. This requires knowledge of the priority risk species or taxonomic groups for which eDNA surveillance will be informative, validated eDNA assays for those species or groups, and reference DNA sequences for both target non-native and related native Antarctic species. Here, we used an expert elicitation process and decision-by-consensus approach to identify and assess priority biosecurity risks for the Australian Antarctic Program (AAP) in East Antarctica, including identifying high priority non-native species and their potential transport pathways. We determined that the priority targets for biosecurity monitoring were not individual species, but rather broader taxonomic groups such as mussels (Mytilus species), tunicates (Ascidiacea), springtails (Collembola), and grasses (Poaceae). These groups each include multiple species with high risks of introduction to and/or establishment in Antarctica. The most appropriate eDNA methods for the AAP must be capable of detecting a range of species within these high-risk groups (e.g., eDNA metabarcoding). We conclude that the most beneficial Antarctic eDNA biosecurity applications include surveillance of marine species in nearshore environments, terrestrial invertebrates, and biofouling species on vessels visiting Antarctica. An urgent need exists to identify suitable genetic markers for detecting priority species groups, establish baseline terrestrial and marine biodiversity for Antarctic stations, and develop eDNA sampling methods for detecting biofouling organisms.

year: 2023-09-01

title: Te kiri ka tōkia e te anu: Ko ētahi āhuatanga ki ngā kāinga o Hiruhārama me Te Horo

authors: Parata, Patricia Hekia

subjects: Tangihanga

abstract: He mea waihanga e ahau, tēnei tuhituhinga, i runga i tēnei whakaaro, kia tirohia te hanga, me te āhua o te tangihanga, ki ōku marae e rua, o roto o Ngāti Porou, kei Hiruhārama me Te Horo. Kāore i whāia he wāhanga ki ngā pūtakenga mai o ngā tikanga. Engari, he mea tātaki haere noa iho ko ngā kaupapa tauira o ēnei tikanga. 
He mea raranga anō ngā kōrero nei, kia whiri ai i roto i ngā tauira kōrero nei, te tūpāpaku, te marae, ngā tāngata me ngā tikanga, e pā ana ki a rātau katoa. 
Ahakoa te nui, te huhua noa iho, o ngā tuhituhinga mō te āhua ki tēnei mea, ki te marae, te whaikōrero, te tangihanga, ēnei mea katoa, kore rawa anō nei, tētahi paku tuhituhi kua whakatakotoria i tēnei hanga nei. Ehara hoki tēnei i te tuhituhinga e whai ana i te āhua o ērā o mua atu. 
He mea kohikohi ēnei kōrero, nā ētahi kuia, me ētahi kaumātua, me ngā mea pakeke o tōku nei rohe, ā, he aronga nui nāku ki ngā mea i kite ai au i ngā wā i ahau i te kāinga, me ngā hui i tae ai au mai anō i tōku tamarikitanga. Nō reira, he whakapūteatanga ēnei mea katoa, nō ngā mea katoa i runga ake nei. 
Kua wehewehengia ēnei kōrero kia takoto pēnei ana nā: ko te wāhanga tuatahi, ko te takenga mai o Ngāti Porou, me ngā wehewehenga mai o ngā hapū; ko te wāhanga tuarua, e pā ana ki ngā whakamārama o ngā kupu, arā, te kirimate, te paemate, me te wharemate; tuatoru, ko te whakahoki o te tūpāpaku; tuawhā, kei ngā mahi ki runga i te marae; tuarima, ngā tikanga o te rā nehu; tuaono, ngā mahi whakatutuki. 
Hei whakamutu ake, kua whakarārangitia e ahau, ngā roherohenga mahi, me ngā tūranga e rite ana mō tēnā, mō tēnā, mō tēnā.

text: Te kiri ka tōkia e te anu: Ko ētahi āhuatanga ki ngā kāinga o Hiruhārama me Te Horo He mea waihanga e ahau, tēnei tuhituhinga, i runga i tēnei whakaaro, kia tirohia te hanga, me te āhua o te tangihanga, ki ōku marae e rua, o roto o Ngāti Porou, kei Hiruhārama me Te Horo. Kāore i whāia he wāhanga ki ngā pūtakenga mai o ngā tikanga. Engari, he mea tātaki haere noa iho ko ngā kaupapa tauira o ēnei tikanga. 
He mea raranga anō ngā kōrero nei, kia whiri ai i roto i ngā tauira kōrero nei, te tūpāpaku, te marae, ngā tāngata me ngā tikanga, e pā ana ki a rātau katoa. 
Ahakoa te nui, te huhua noa iho, o ngā tuhituhinga mō te āhua ki tēnei mea, ki te marae, te whaikōrero, te tangihanga, ēnei mea katoa, kore rawa anō nei, tētahi paku tuhituhi kua whakatakotoria i tēnei hanga nei. Ehara hoki tēnei i te tuhituhinga e whai ana i te āhua o ērā o mua atu. 
He mea kohikohi ēnei kōrero, nā ētahi kuia, me ētahi kaumātua, me ngā mea pakeke o tōku nei rohe, ā, he aronga nui nāku ki ngā mea i kite ai au i ngā wā i ahau i te kāinga, me ngā hui i tae ai au mai anō i tōku tamarikitanga. Nō reira, he whakapūteatanga ēnei mea katoa, nō ngā mea katoa i runga ake nei. 
Kua wehewehengia ēnei kōrero kia takoto pēnei ana nā: ko te wāhanga tuatahi, ko te takenga mai o Ngāti Porou, me ngā wehewehenga mai o ngā hapū; ko te wāhanga tuarua, e pā ana ki ngā whakamārama o ngā kupu, arā, te kirimate, te paemate, me te wharemate; tuatoru, ko te whakahoki o te tūpāpaku; tuawhā, kei ngā mahi ki runga i te marae; tuarima, ngā tikanga o te rā nehu; tuaono, ngā mahi whakatutuki. 
Hei whakamutu ake, kua whakarārangitia e ahau, ngā roherohenga mahi, me ngā tūranga e rite ana mō tēnā, mō tēnā, mō tēnā.

year: 1983