title: Transition metal availability to speleothems controlled by organic binding ligands

authors: Hartland, Adam

subjects: Science & Technology

abstract: Speleothems are important archives of Quaternary palaeoclimate. However, climate proxies based on trace elements in speleothems are currently limited to the metals which exhibit simple partitioning (Mg²⁺, Sr²⁺, Ba²⁺). This study aims to expand understanding of the processes controlling the divalent first row transition metals (M²⁺) in these systems. Adsorptive cathodic stripping voltammetry was used to determine Cu speciation in speleothem dripwater, stream and pool samples from five limestone caves located in diverse climatic settings. Our results demonstrate that Cu binding and stabilisation by organic ligands (L) is a universal property of cave waters, which decreases the available Cu concentration ([Cu’]) by ~5 orders of magnitude relative to total Cu concentration ([CuT]). Furthermore, [Cu’] does not change meaningfully with increases in either [CuT] or [L], meaning that Cu²⁺ substitution in Ca²⁺ valence sites in precipitating CaCO₃ speleothems is likely to be inhibited by organic complexation. We suggest that the residence time of speleothem thin water films (1/drip rate), the dissociation rates of labile metal-organic complexes, and the stability of adsorbed (ternary) metal-organic complexes will determine M²⁺ incorporation in speleothems.

text: Transition metal availability to speleothems controlled by organic binding ligands Speleothems are important archives of Quaternary palaeoclimate. However, climate proxies based on trace elements in speleothems are currently limited to the metals which exhibit simple partitioning (Mg²⁺, Sr²⁺, Ba²⁺). This study aims to expand understanding of the processes controlling the divalent first row transition metals (M²⁺) in these systems. Adsorptive cathodic stripping voltammetry was used to determine Cu speciation in speleothem dripwater, stream and pool samples from five limestone caves located in diverse climatic settings. Our results demonstrate that Cu binding and stabilisation by organic ligands (L) is a universal property of cave waters, which decreases the available Cu concentration ([Cu’]) by ~5 orders of magnitude relative to total Cu concentration ([CuT]). Furthermore, [Cu’] does not change meaningfully with increases in either [CuT] or [L], meaning that Cu²⁺ substitution in Ca²⁺ valence sites in precipitating CaCO₃ speleothems is likely to be inhibited by organic complexation. We suggest that the residence time of speleothem thin water films (1/drip rate), the dissociation rates of labile metal-organic complexes, and the stability of adsorbed (ternary) metal-organic complexes will determine M²⁺ incorporation in speleothems.

year: 2018

title: Work attitudes and well-being among virtual workers

authors: Witzel, Marisa

subjects: virtual work

abstract: The present study examined how certain characteristics of flexible work, the home environment, and the individual impact the outcomes of work-family conflict, job satisfaction, organisational commitment, and psychological strain.  
	A questionnaire measuring perceptions of control, flexibility, job involvement, family involvement, work to family and family to work conflict, organisational commitment, job satisfaction, family support, physical boundaries, workplace isolation, psychological strain, personality, and demographic information was created and posted online.  An email was circulated to 390 virtual sales employees from one large organisation in the United States inviting them to participate in the study, and 278 people responded.  
Results identified characteristics of the type of work, work enivronment, and the individual that are predictive of individual and organisational outcomes. Findings supported hypotheses that control, flexibility, and family support positively impact the outcomes of conflict, satisfaction, and strain for virtual workers.  Job involvement was found as predicted to positively impact work to family conflict, and family involvement was positively related to family to work conflict.  Contrary to predictions, a negative relationship was found between job involvement and strain, suggesting that those who identify more highly with their job also 
experience less strain. Consistent with earlier studies, workplace isolation was associated with reduced job satisfaction and organisational commitment (Marshall, Michaels, and Mulki, 2007). In line with boundary theory (Voydanoff, 2005), it was hypothesised that the presence of physical boundaries between work and non work domains would significantly impact measures of conflict and strain for virtual workers. However, results indicated no significant effects.
A comparison of perceptions of work-family conflict between individuals with children at home and those without illustrated no significant differences between employees with children at home and those without.  Speculated explanations for inconsistent findings are addressed in the discussion chapter.
	Work to family conflict was predicted to mediate the relationship between flexibility and job satisfaction for virtual workers, and analysis supported the presence of partial mediation.  Family to work conflict was also predicted to mediate the flexibility and job satisfaction relationship, however, results were not significant in this case.  Uses of workspace (i.e. for work, leisure, family activities, etc.) were tested as mediator for the relationship between family to work conflict and job satisfaction, and results did not support a mediation effect.  
	In sum, findings of this study identify sources of both positive and negative outcomes for people working from home.  Although individuals' experiences working virtually differ greatly, this study identifies common  
challenges and issues they face.  By pinpointing the sources of conflict, satisfaction, commitment, and strain in the home office, organisations and individuals can take steps to protect workers against negative outcomes, and maximise positive outcomes.  Implications and limitations of this study are discussed in the final chapter.

text: Work attitudes and well-being among virtual workers The present study examined how certain characteristics of flexible work, the home environment, and the individual impact the outcomes of work-family conflict, job satisfaction, organisational commitment, and psychological strain.  
	A questionnaire measuring perceptions of control, flexibility, job involvement, family involvement, work to family and family to work conflict, organisational commitment, job satisfaction, family support, physical boundaries, workplace isolation, psychological strain, personality, and demographic information was created and posted online.  An email was circulated to 390 virtual sales employees from one large organisation in the United States inviting them to participate in the study, and 278 people responded.  
Results identified characteristics of the type of work, work enivronment, and the individual that are predictive of individual and organisational outcomes. Findings supported hypotheses that control, flexibility, and family support positively impact the outcomes of conflict, satisfaction, and strain for virtual workers.  Job involvement was found as predicted to positively impact work to family conflict, and family involvement was positively related to family to work conflict.  Contrary to predictions, a negative relationship was found between job involvement and strain, suggesting that those who identify more highly with their job also 
experience less strain. Consistent with earlier studies, workplace isolation was associated with reduced job satisfaction and organisational commitment (Marshall, Michaels, and Mulki, 2007). In line with boundary theory (Voydanoff, 2005), it was hypothesised that the presence of physical boundaries between work and non work domains would significantly impact measures of conflict and strain for virtual workers. However, results indicated no significant effects.
A comparison of perceptions of work-family conflict between individuals with children at home and those without illustrated no significant differences between employees with children at home and those without.  Speculated explanations for inconsistent findings are addressed in the discussion chapter.
	Work to family conflict was predicted to mediate the relationship between flexibility and job satisfaction for virtual workers, and analysis supported the presence of partial mediation.  Family to work conflict was also predicted to mediate the flexibility and job satisfaction relationship, however, results were not significant in this case.  Uses of workspace (i.e. for work, leisure, family activities, etc.) were tested as mediator for the relationship between family to work conflict and job satisfaction, and results did not support a mediation effect.  
	In sum, findings of this study identify sources of both positive and negative outcomes for people working from home.  Although individuals' experiences working virtually differ greatly, this study identifies common  
challenges and issues they face.  By pinpointing the sources of conflict, satisfaction, commitment, and strain in the home office, organisations and individuals can take steps to protect workers against negative outcomes, and maximise positive outcomes.  Implications and limitations of this study are discussed in the final chapter.

year: 2008

title: Holding a mirror to society? Sociodemographic diversity within clinical psychology training programmes across Aotearoa.

authors: Scarf, Damian

subjects: Education, Medical

abstract: It has recently been demonstrated by Crampton et al that there has been a marked increase in the sociodemographic diversity of the University of Otago’s health professional programmes between 2010 and 2016.1 This change is evidenced by the fact that a historic 76 health professional Māori graduates crossed the Dunedin Town Hall stage in December 2018. A key driver of this change was the University of Otago’s Division of Health Sciences Mirror on Society selection policy. Here, by documenting the sociodemographic diversity of an equally important professional programme, clinical psychology, we highlight the need for similar selection policies to be implemented Aotearoa/New Zealand wide.

text: Holding a mirror to society? Sociodemographic diversity within clinical psychology training programmes across Aotearoa. It has recently been demonstrated by Crampton et al that there has been a marked increase in the sociodemographic diversity of the University of Otago’s health professional programmes between 2010 and 2016.1 This change is evidenced by the fact that a historic 76 health professional Māori graduates crossed the Dunedin Town Hall stage in December 2018. A key driver of this change was the University of Otago’s Division of Health Sciences Mirror on Society selection policy. Here, by documenting the sociodemographic diversity of an equally important professional programme, clinical psychology, we highlight the need for similar selection policies to be implemented Aotearoa/New Zealand wide.

year: 2019