title: Flow cytometric characterization of freshwater crayfish hemocytes for the examination of physiological status in wild and captive animals

authors: Taylor, Sean

subjects: New Zealand

abstract: Enumeration of invertebrate hemocytes is a potentially powerful tool for the determination of physiological effects of extrinsic stressors, such as hypoxia, disease, and toxicant exposure. A detailed flow cytometric method of broad application was developed for the objective characterization and enumeration of the hemocytes of New Zealand freshwater crayfish Paranephrops planifrons for the purpose of physiological health assessment. Hemocyte populations were isolated by flow cytometric sorting based on differential light scatter properties followed by morphological characterization via light microscopy and software image analysis. Cells were identified as hyaline, semigranular, and granular hemocytes based on established invertebrate hemocyte classification. A characteristic decrease in nuclear size, an increase in granularity between the hyaline and granular cells, and the eccentric location of nuclei in granular cells were also observed. The granulocyte subpopulations were observed to possess varying degrees of granularity. The developed methodology was used to perform total and differential hemocyte counts from three lake populations and between wild and captive crayfish specimens. Differences in total and differential hemocyte counts were not observed among the wild populations. However, specimens held in captivity for 14 d exhibited a significant 63% reduction in total hemocyte count, whereas the relative hemocyte proportions remained the same. These results demonstrate the utility of this method for the investigation of subacute stressor effects in selected decapod crustaceans.

text: Flow cytometric characterization of freshwater crayfish hemocytes for the examination of physiological status in wild and captive animals Enumeration of invertebrate hemocytes is a potentially powerful tool for the determination of physiological effects of extrinsic stressors, such as hypoxia, disease, and toxicant exposure. A detailed flow cytometric method of broad application was developed for the objective characterization and enumeration of the hemocytes of New Zealand freshwater crayfish Paranephrops planifrons for the purpose of physiological health assessment. Hemocyte populations were isolated by flow cytometric sorting based on differential light scatter properties followed by morphological characterization via light microscopy and software image analysis. Cells were identified as hyaline, semigranular, and granular hemocytes based on established invertebrate hemocyte classification. A characteristic decrease in nuclear size, an increase in granularity between the hyaline and granular cells, and the eccentric location of nuclei in granular cells were also observed. The granulocyte subpopulations were observed to possess varying degrees of granularity. The developed methodology was used to perform total and differential hemocyte counts from three lake populations and between wild and captive crayfish specimens. Differences in total and differential hemocyte counts were not observed among the wild populations. However, specimens held in captivity for 14 d exhibited a significant 63% reduction in total hemocyte count, whereas the relative hemocyte proportions remained the same. These results demonstrate the utility of this method for the investigation of subacute stressor effects in selected decapod crustaceans.

year: 2009

title: Dynamic landscape, dynamic practice: Aboriginal dwelling beside the Carran Carran–Durt’yowan floodplains (Thomson River–Latrobe River, Central Gippsland)

authors: Anderson, William

abstract: Recurring occupation beside waterways is an essential part of Aboriginal dwelling and movement in the landscape. Riverbanks and their wider floodplains were repeatedly inhabited as hunting and fishing grounds and to gather plants and other materials; moreover, Aboriginal people used rivers and creeks as routeways and landmarks to navigate Country, for meetings and ceremonies, to affirm boundaries and territorial claims; and they were sacred features whose origins were captured in stories and songs. Archaeological investigations often encounter material that hints at persistent occupation of riverine landforms, but it is rare to conclusively prove the overall duration that a place was inhabited and the length of occupation episodes. Excavations near Sale in central Gippsland, in GunaiKurnai Country, identified one such place. Cultural deposits buried in the sands of an alluvial rise at Fulham include hearths and concentrations of stone artefacts up to a metre deep. Radiocarbon dating shows two distinct occupation phases—in the Late Pleistocene and Holocene eras—that were separated by a gap of up to eight thousand years. The results underline the enduring significance of the alluvial plains around the confluence of Carran Carran (Thomson River) and Durt’yowan (Latrobe River) and show habitation by GunaiKurnai Ancestors over vast timespans as the climate, water level, landforms and ecology of the wider estuarine district changed. They highlight spatial and temporal connections between the upper and lower reaches of these river systems over several millennia, giving a unique, long–term perspective on human responses to shifts in climate and water flows.

text: Dynamic landscape, dynamic practice: Aboriginal dwelling beside the Carran Carran–Durt’yowan floodplains (Thomson River–Latrobe River, Central Gippsland) Recurring occupation beside waterways is an essential part of Aboriginal dwelling and movement in the landscape. Riverbanks and their wider floodplains were repeatedly inhabited as hunting and fishing grounds and to gather plants and other materials; moreover, Aboriginal people used rivers and creeks as routeways and landmarks to navigate Country, for meetings and ceremonies, to affirm boundaries and territorial claims; and they were sacred features whose origins were captured in stories and songs. Archaeological investigations often encounter material that hints at persistent occupation of riverine landforms, but it is rare to conclusively prove the overall duration that a place was inhabited and the length of occupation episodes. Excavations near Sale in central Gippsland, in GunaiKurnai Country, identified one such place. Cultural deposits buried in the sands of an alluvial rise at Fulham include hearths and concentrations of stone artefacts up to a metre deep. Radiocarbon dating shows two distinct occupation phases—in the Late Pleistocene and Holocene eras—that were separated by a gap of up to eight thousand years. The results underline the enduring significance of the alluvial plains around the confluence of Carran Carran (Thomson River) and Durt’yowan (Latrobe River) and show habitation by GunaiKurnai Ancestors over vast timespans as the climate, water level, landforms and ecology of the wider estuarine district changed. They highlight spatial and temporal connections between the upper and lower reaches of these river systems over several millennia, giving a unique, long–term perspective on human responses to shifts in climate and water flows.

year: 2021

title: A Maori and Psychology Research Unit

authors: Nikora, Linda Waimarie

subjects: Maori

abstract: Little psychological information and few applications have been informed by Maori centred research. The psychological research base available to support prevention or change strategies aimed at Maori is almost non-existent. Most information and applications are imported from outside of Aotearoa/New Zealand and are seldom subjected to vetting procedures to ensure adequacy and appropriateness. Even though numbers have changed slightly in the last 10 years, there are still too few Maori in the professional ranks of psychology, both as practitioners, teachers and researchers. More of everything is needed, and it was needed yesterday. At the University of Waikato, staff of the Psychology Department have recognised the need to support positive changes to rectify that situation described above.

This paper describes the fledgling development of a Maori and Psychology Research Unit and how it is intended to promote Maori centred-research, Maori-partnership research, and the scholarly development of Maori professionals. The first section deals with issues and challenges the MPRU expects to face in its development and is written by the first author. The second section describes the nature of learning and support that the MPRU will afford to a new generation of Maori researchers and scholars within the discipline of psychology. This section is written by the second author.

text: A Maori and Psychology Research Unit Little psychological information and few applications have been informed by Maori centred research. The psychological research base available to support prevention or change strategies aimed at Maori is almost non-existent. Most information and applications are imported from outside of Aotearoa/New Zealand and are seldom subjected to vetting procedures to ensure adequacy and appropriateness. Even though numbers have changed slightly in the last 10 years, there are still too few Maori in the professional ranks of psychology, both as practitioners, teachers and researchers. More of everything is needed, and it was needed yesterday. At the University of Waikato, staff of the Psychology Department have recognised the need to support positive changes to rectify that situation described above.

This paper describes the fledgling development of a Maori and Psychology Research Unit and how it is intended to promote Maori centred-research, Maori-partnership research, and the scholarly development of Maori professionals. The first section deals with issues and challenges the MPRU expects to face in its development and is written by the first author. The second section describes the nature of learning and support that the MPRU will afford to a new generation of Maori researchers and scholars within the discipline of psychology. This section is written by the second author.

year: 1998-07-01