title: Research tropospheres: assemblages of cows, sharemilkers and researcher in Aotearoa New Zealand

authors: Adams-Hutcheson, Gail

abstract: Cresswell (2011) broadens mobility studies to include non-human objects and structures, but rarely, non-human animals and the weather. I add here both livestock and the more literal atmospheric conditions of sun, wind and rain which are largely missing from mobilities studies. Weather is ubiquitous, yet hard to ignore – it impacts on both researcher and the researched. I visited farms and was: jumped-up-on by dogs, rode on 4-wheel bikes, got licked by calves [happy/sunny], felt hot, got covered in dust [tired/sweltering], stood still in the milking-shed [tension/cold], and was blasted by freezing winds and slopped through thick mud [depression/winter wet]. For Ash (2013a, 35) "the body is a kind of living or somatic memory, which is composed of various retentional apparatuses", which become ignited by alignment of senses. In this paper I argue for attention to be paid to sharemilking and the materiality of atmospheres to draw attention to the 'centrifugal' forces of mobile rural dwelling. Sharemilking is a largely unique agrarian practice in New Zealand which is embedded in the notion of mobility. Sharemilkers typically own the livestock and machinery, but not the land and enter into contract with landowners on a share profit basis. Contracts are finished and new ones are taken up on a set day, the 1st June which is often termed colloquially as 'Gypsy-day'. The contract nature of sharemilking stimulates a cascade of mobilities and enabling infrastructures (assemblages) as farmers move on a stuttering schedule of contract renewals.

text: Research tropospheres: assemblages of cows, sharemilkers and researcher in Aotearoa New Zealand Cresswell (2011) broadens mobility studies to include non-human objects and structures, but rarely, non-human animals and the weather. I add here both livestock and the more literal atmospheric conditions of sun, wind and rain which are largely missing from mobilities studies. Weather is ubiquitous, yet hard to ignore – it impacts on both researcher and the researched. I visited farms and was: jumped-up-on by dogs, rode on 4-wheel bikes, got licked by calves [happy/sunny], felt hot, got covered in dust [tired/sweltering], stood still in the milking-shed [tension/cold], and was blasted by freezing winds and slopped through thick mud [depression/winter wet]. For Ash (2013a, 35) "the body is a kind of living or somatic memory, which is composed of various retentional apparatuses", which become ignited by alignment of senses. In this paper I argue for attention to be paid to sharemilking and the materiality of atmospheres to draw attention to the 'centrifugal' forces of mobile rural dwelling. Sharemilking is a largely unique agrarian practice in New Zealand which is embedded in the notion of mobility. Sharemilkers typically own the livestock and machinery, but not the land and enter into contract with landowners on a share profit basis. Contracts are finished and new ones are taken up on a set day, the 1st June which is often termed colloquially as 'Gypsy-day'. The contract nature of sharemilking stimulates a cascade of mobilities and enabling infrastructures (assemblages) as farmers move on a stuttering schedule of contract renewals.

year: 2017

title: Two thermostable hemicellulases and their effects on wood pulps

authors: Bicho, Paul A.

abstract: Two hemicellulases, cloned from a thermophilic anaerobe (isolate TP8 6.3.3.1) were partially purified and characterised. The ability of these enzymes to hydrolyse the hemicellulose components of various types of pulps and their effects on the bleachability of radiata pine kraft pulp were examined. The xylanase (two preparations) and mannanase had broad pH optima (6-7.5). The xylanases had temperature optima of 70°C (10 min assay) and the mannanase had an optimum of 80°C (10 min assay). All the cloned enzymes were thermostable with more than 95% of the enzyme activity remaining after 24 hours at 70°C, in an unbuffered solution. Buffering affected the thermostability of the enzymes. The mannanase had a half life of 48 min at 85°C. The xylanases were able to hydrolyse xylans but also had a pH-dependent CM cellulase activity, but this was never more than 10% of the xylanase activity. The mannanase hydrolysed mannan, glucomannans and galactomannans. The glucose content of the glucomannans had little or no effect on mannanase activity but the galactose substituents of the galactomannans severely inhibited the hydrolysis of these substrates.

The thermostable xylanase hydrolysed more than 75% of soluble radiata pine xylan to low molecular weight (< DP10) xylo-oligomers. These included; xylose, xylobiose, xylotriose, arabinose-substituted xylobiose and xylotriose and 4-O-methyl glucuronic acid substituted xylotrioses. The arabinose substituents were bound to the terminal, non-reducing xylose residue; the glucuronic acid substituents may be bound to the non-reducing or central xylose residues of the substituted xylotriose. The thermostable mannanase also hydrolysed more than 75% of soluble radiata glucomannan, producing mannose, mannobiose, mannotriose, glucomannose and glucomannobiose.

The hemicellulases were used to treat (at 70°C, 24 hr) a variety of wood pulps, including kraft (softwood and hardwood), radiata NSAQ pulp, radiata CTMP and radiata TMP. Both enzymes solubilised their respective substrates from these pulps. The chemical pulps were more susceptible to enzymatic attack than the mechanical pulps, possibly due to the greater fibre porosity of the chemical pulps. The xylanase solubilised ~4% of the xylan and the mannanase solubilised 10% of the glucomannan from radiata kraft pulp. In comparison with other xylanases, the thermostable xylanase was less effective in solubilising xylan from kraft pulps. The hemicelluloses of kraft pulps that had been enzyme treated were extracted. The extracted xylan from the xylanase-treated pulp was lower in average DP than the xylan extracted from untreated pulps. The average DP of the extracted glucomannan from the mannanase-treated pulps was no different than that of glucomannans extracted from untreated pulps. The extracted xylan and glucomannan from untreated kraft pulps were readily hydrolysed by the xylanase and the mannanase respectively, suggesting that enzyme inaccessibility to the substrate within the fibre wall was the main cause of their resistance to enzymatic attack.

The effect of these enzymes on the bleachability of radiata kraft pulps was studied by measuring the reduction in kappa number (κ), relative to untreated controls, after a standard D/C E prebleaching sequence. The xylanase and the mannanase had little or no effect on the bleachability of radiata kraft pulps. Xylanase treated kraft pulp required a protease treatment after the hemicellulose treatment but before bleaching, in order to elicit any improvement in bleachability (~7% drop in κ relative to untreated control pulps). Mannanase treated kraft pulp showed no improvement in bleachability. For comparison commercial xylanases (including a thermostable xylanase) were used to treat radiata kraft pulps and did improve bleachability significantly. These enzymes also solubilised three to four times more xylan than the cloned, thermostable xylanase. Therefore, the ineffectiveness of the cloned xylanase may be due to its very limited ability to hydrolyse intra-fibril xylan in kraft pulp fibres.

text: Two thermostable hemicellulases and their effects on wood pulps Two hemicellulases, cloned from a thermophilic anaerobe (isolate TP8 6.3.3.1) were partially purified and characterised. The ability of these enzymes to hydrolyse the hemicellulose components of various types of pulps and their effects on the bleachability of radiata pine kraft pulp were examined. The xylanase (two preparations) and mannanase had broad pH optima (6-7.5). The xylanases had temperature optima of 70°C (10 min assay) and the mannanase had an optimum of 80°C (10 min assay). All the cloned enzymes were thermostable with more than 95% of the enzyme activity remaining after 24 hours at 70°C, in an unbuffered solution. Buffering affected the thermostability of the enzymes. The mannanase had a half life of 48 min at 85°C. The xylanases were able to hydrolyse xylans but also had a pH-dependent CM cellulase activity, but this was never more than 10% of the xylanase activity. The mannanase hydrolysed mannan, glucomannans and galactomannans. The glucose content of the glucomannans had little or no effect on mannanase activity but the galactose substituents of the galactomannans severely inhibited the hydrolysis of these substrates.

The thermostable xylanase hydrolysed more than 75% of soluble radiata pine xylan to low molecular weight (< DP10) xylo-oligomers. These included; xylose, xylobiose, xylotriose, arabinose-substituted xylobiose and xylotriose and 4-O-methyl glucuronic acid substituted xylotrioses. The arabinose substituents were bound to the terminal, non-reducing xylose residue; the glucuronic acid substituents may be bound to the non-reducing or central xylose residues of the substituted xylotriose. The thermostable mannanase also hydrolysed more than 75% of soluble radiata glucomannan, producing mannose, mannobiose, mannotriose, glucomannose and glucomannobiose.

The hemicellulases were used to treat (at 70°C, 24 hr) a variety of wood pulps, including kraft (softwood and hardwood), radiata NSAQ pulp, radiata CTMP and radiata TMP. Both enzymes solubilised their respective substrates from these pulps. The chemical pulps were more susceptible to enzymatic attack than the mechanical pulps, possibly due to the greater fibre porosity of the chemical pulps. The xylanase solubilised ~4% of the xylan and the mannanase solubilised 10% of the glucomannan from radiata kraft pulp. In comparison with other xylanases, the thermostable xylanase was less effective in solubilising xylan from kraft pulps. The hemicelluloses of kraft pulps that had been enzyme treated were extracted. The extracted xylan from the xylanase-treated pulp was lower in average DP than the xylan extracted from untreated pulps. The average DP of the extracted glucomannan from the mannanase-treated pulps was no different than that of glucomannans extracted from untreated pulps. The extracted xylan and glucomannan from untreated kraft pulps were readily hydrolysed by the xylanase and the mannanase respectively, suggesting that enzyme inaccessibility to the substrate within the fibre wall was the main cause of their resistance to enzymatic attack.

The effect of these enzymes on the bleachability of radiata kraft pulps was studied by measuring the reduction in kappa number (κ), relative to untreated controls, after a standard D/C E prebleaching sequence. The xylanase and the mannanase had little or no effect on the bleachability of radiata kraft pulps. Xylanase treated kraft pulp required a protease treatment after the hemicellulose treatment but before bleaching, in order to elicit any improvement in bleachability (~7% drop in κ relative to untreated control pulps). Mannanase treated kraft pulp showed no improvement in bleachability. For comparison commercial xylanases (including a thermostable xylanase) were used to treat radiata kraft pulps and did improve bleachability significantly. These enzymes also solubilised three to four times more xylan than the cloned, thermostable xylanase. Therefore, the ineffectiveness of the cloned xylanase may be due to its very limited ability to hydrolyse intra-fibril xylan in kraft pulp fibres.

year: 1992

title: Ngā kanohi hou – identifying and exploring the issues: Experiences of an intern

authors: Masters-Awatere, Bridgette

subjects: Maori

abstract: The current paper reflects upon the discovery of an intern from the post graduate diploma in community psychology programme (PGDipPsych (Com). The PGDipPsych (Com) is currently facilitated through the University of Waikato School of Arts and Social Sciences, Psychology Department. This journey of discovery is presented from the perspective of a Māori student who is employed in a mainstream public health organisation. The perspective of a person who is new to the workforce, and the “real world,” who views the surrounding environment with a pair of fresh eyes.

This paper highlights the importance of the internship period as it supports the student who moves from a structured environment with a strong emphasis on theory, towards a competitive, semi structured environment that is driven by deadlines, budgets and contracts.

Factors identified are the demands of Māori communities on Māori health researchers, supportive versus competitive environments, the benefits and drawbacks of being based in a mainstream health organisation, and the future direction of Māori health research. It is hoped that the current paper will encourage further discussion about the future direction of a diploma programme such as the PGDipPsychCom for Māori graduates of a New Zealand tertiary institution.

text: Ngā kanohi hou – identifying and exploring the issues: Experiences of an intern The current paper reflects upon the discovery of an intern from the post graduate diploma in community psychology programme (PGDipPsych (Com). The PGDipPsych (Com) is currently facilitated through the University of Waikato School of Arts and Social Sciences, Psychology Department. This journey of discovery is presented from the perspective of a Māori student who is employed in a mainstream public health organisation. The perspective of a person who is new to the workforce, and the “real world,” who views the surrounding environment with a pair of fresh eyes.

This paper highlights the importance of the internship period as it supports the student who moves from a structured environment with a strong emphasis on theory, towards a competitive, semi structured environment that is driven by deadlines, budgets and contracts.

Factors identified are the demands of Māori communities on Māori health researchers, supportive versus competitive environments, the benefits and drawbacks of being based in a mainstream health organisation, and the future direction of Māori health research. It is hoped that the current paper will encourage further discussion about the future direction of a diploma programme such as the PGDipPsychCom for Māori graduates of a New Zealand tertiary institution.

year: 1999