title: Potent toxins in Arctic environments – Presence of saxitoxins and an unusual microcystin variant in Arctic freshwater ecosystems

authors: Kleinteich, Julia

abstract: Cyanobacteria are the predominant phototrophs in freshwater ecosystems of the polar regions where they commonly form extensive benthic mats. Despite their major biological role in these ecosystems, little attention has been paid to their physiology and biochemistry. An important feature of cyanobacteria from the temperate and tropical regions is the production of a large variety of toxic secondary metabolites. In Antarctica, and more recently in the Arctic, the cyanobacterial toxins microcystin and nodularin (Antarctic only) have been detected in freshwater microbial mats. To date other cyanobacterial toxins have not been reported from these locations. Five Arctic cyanobacterial communities were screened for saxitoxin, another common cyanobacterial toxin, and microcystins using immunological, spectroscopic and molecular methods. Saxitoxin was detected for the first time in cyanobacteria from the Arctic. In addition, an unusual microcystin variant was identified using liquid chromatography–mass spectrometry. Gene expression analyses confirmed the analytical findings, whereby parts of the sxt and mcy operon involved in saxitoxin and microcystin synthesis, were detected and sequenced in one and five of the Arctic cyanobacterial samples, respectively. The detection of these compounds in the cryosphere improves the understanding of the biogeography and distribution of toxic cyanobacteria globally. The sequences of sxt and mcy genes provided from this habitat for the first time may help to clarify the evolutionary origin of toxin production in cyanobacteria.

text: Potent toxins in Arctic environments – Presence of saxitoxins and an unusual microcystin variant in Arctic freshwater ecosystems Cyanobacteria are the predominant phototrophs in freshwater ecosystems of the polar regions where they commonly form extensive benthic mats. Despite their major biological role in these ecosystems, little attention has been paid to their physiology and biochemistry. An important feature of cyanobacteria from the temperate and tropical regions is the production of a large variety of toxic secondary metabolites. In Antarctica, and more recently in the Arctic, the cyanobacterial toxins microcystin and nodularin (Antarctic only) have been detected in freshwater microbial mats. To date other cyanobacterial toxins have not been reported from these locations. Five Arctic cyanobacterial communities were screened for saxitoxin, another common cyanobacterial toxin, and microcystins using immunological, spectroscopic and molecular methods. Saxitoxin was detected for the first time in cyanobacteria from the Arctic. In addition, an unusual microcystin variant was identified using liquid chromatography–mass spectrometry. Gene expression analyses confirmed the analytical findings, whereby parts of the sxt and mcy operon involved in saxitoxin and microcystin synthesis, were detected and sequenced in one and five of the Arctic cyanobacterial samples, respectively. The detection of these compounds in the cryosphere improves the understanding of the biogeography and distribution of toxic cyanobacteria globally. The sequences of sxt and mcy genes provided from this habitat for the first time may help to clarify the evolutionary origin of toxin production in cyanobacteria.

year: 2013

title: A user-centered design of a personal digital library for music exploration

authors: Bainbridge, David

subjects: computer science

abstract: We describe the evaluation of a personal digital library environment designed to help musicians capture, enrich and store their ideas using a spatial hypermedia paradigm. The target user group is musicians who primarily use audio and text for composition and arrangement, rather than with formal music notation. Using the principle of user-centered design, the software implementation was guided by a diary study involving nine musicians which suggested five requirements for the software to support: capturing, overdubbing, developing, storing, and organizing. Moreover, the underlying spatial data-model was exploited to give raw audio compositions a hierarchical structure, and - to aid musicians in retrieving previous ideas - a search facility is available to support both query by humming and text-based queries. A user evaluation of the completed design with eleven subjects indicated that musicians, in general, would find the hypermedia environment useful for capturing and managing their moments of musical creativity and exploration. More specifically they would make use of the query by humming facility and the hierarchical track organization, but not the overdubbing facility as implemented.

text: A user-centered design of a personal digital library for music exploration We describe the evaluation of a personal digital library environment designed to help musicians capture, enrich and store their ideas using a spatial hypermedia paradigm. The target user group is musicians who primarily use audio and text for composition and arrangement, rather than with formal music notation. Using the principle of user-centered design, the software implementation was guided by a diary study involving nine musicians which suggested five requirements for the software to support: capturing, overdubbing, developing, storing, and organizing. Moreover, the underlying spatial data-model was exploited to give raw audio compositions a hierarchical structure, and - to aid musicians in retrieving previous ideas - a search facility is available to support both query by humming and text-based queries. A user evaluation of the completed design with eleven subjects indicated that musicians, in general, would find the hypermedia environment useful for capturing and managing their moments of musical creativity and exploration. More specifically they would make use of the query by humming facility and the hierarchical track organization, but not the overdubbing facility as implemented.

year: 2010

title: Problem based learning and New Zealand legal education

authors: Mackinnon, Jacquelin

subjects: law

abstract: The literature (and e-literature) on Problem Based Learning in Law suggests that this approach has been adopted with enthusiasm by some lecturers in the United Kingdom, Europe and Hong Kong. This article will explore the adoption of PBL approaches through the literature in order to draw some conclusions about the nature of PBL approaches in law and their relationship with institutional approaches to legal education. Problem Based Learning approaches are not visible in New Zealand. The article discusses the reasons for PBL's invisibility and PBL's appropriateness in the New Zealand legal education context now and in the future of legal work. Part of the New Zealand context is the participation of the indigenous people in legal education and consideration is given to whether PBL can benefit Māori law students. 
It is suggested that PBL approaches to learning law promote: 
	Contextualisation
	Interdisciplinarity
	Integration of prior personal and/or professional knowledge
	Collaboration
	Enquiry skills
	Reflection and transition
	Self directed learning and self assessment
	Praxis.

Problem Based Learning requires and fosters reflexive participants, who are sufficiently conceptually literate to read and critique key aspects of the social order and to understand their own, and others' status and role in it. Reflexivity contributes to humanist as well as legal solutions to complex human problems. PBL approaches are consistent with legal education in an increasingly global employment market.

text: Problem based learning and New Zealand legal education The literature (and e-literature) on Problem Based Learning in Law suggests that this approach has been adopted with enthusiasm by some lecturers in the United Kingdom, Europe and Hong Kong. This article will explore the adoption of PBL approaches through the literature in order to draw some conclusions about the nature of PBL approaches in law and their relationship with institutional approaches to legal education. Problem Based Learning approaches are not visible in New Zealand. The article discusses the reasons for PBL's invisibility and PBL's appropriateness in the New Zealand legal education context now and in the future of legal work. Part of the New Zealand context is the participation of the indigenous people in legal education and consideration is given to whether PBL can benefit Māori law students. 
It is suggested that PBL approaches to learning law promote: 
	Contextualisation
	Interdisciplinarity
	Integration of prior personal and/or professional knowledge
	Collaboration
	Enquiry skills
	Reflection and transition
	Self directed learning and self assessment
	Praxis.

Problem Based Learning requires and fosters reflexive participants, who are sufficiently conceptually literate to read and critique key aspects of the social order and to understand their own, and others' status and role in it. Reflexivity contributes to humanist as well as legal solutions to complex human problems. PBL approaches are consistent with legal education in an increasingly global employment market.

year: 2006-06-01