title: Nectary photosynthesis contributes to the production of manuka (Leptospermum scoparium) floral nectar

authors: Clearwater, Michael J.

subjects: Science & Technology

abstract: Current models of floral nectar production do not include a contribution from photosynthesis by green nectary tissue, even though many species have green nectaries. Mānuka (Leptospermum scoparium) floral nectaries are green, and in addition to sugars, their nectar contains dihydroxyacetone (DHA), the precursor of the antimicrobial agent in the honey. We investigated causes of variation in mānuka floral nectar production, particularly the effect of light incident on the nectary.
Flower gas exchange, chlorophyll fluorescence, and the effects on nectar of age, temperature, light, sucrose, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), pyridoxal phosphate, and 13CO2, were measured for attached and excised flowers.
Flower age affected all nectar traits, whilst temperature affected total nectar sugar only. Increased light reduced floral CO2 efflux, increased nectar sugar production, and affected the ratio of DHA to other nectar sugars. DCMU, an inhibitor of photosystem II, reduced nectar sugar production. Pyridoxal phosphate, an inhibitor of the chloroplast envelope triose phosphate transporter, reduced nectar DHA content. Incubation of excised flowers with 13CO2 in the light resulted in enrichment of nectar sugars, including DHA.
Photosynthesis within green nectaries contributes to nectar sugars and influences nectar composition. Mānuka nectar DHA arises from pools of triose phosphate that are modulated by nectary photosynthesis.

text: Nectary photosynthesis contributes to the production of manuka (Leptospermum scoparium) floral nectar Current models of floral nectar production do not include a contribution from photosynthesis by green nectary tissue, even though many species have green nectaries. Mānuka (Leptospermum scoparium) floral nectaries are green, and in addition to sugars, their nectar contains dihydroxyacetone (DHA), the precursor of the antimicrobial agent in the honey. We investigated causes of variation in mānuka floral nectar production, particularly the effect of light incident on the nectary.
Flower gas exchange, chlorophyll fluorescence, and the effects on nectar of age, temperature, light, sucrose, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), pyridoxal phosphate, and 13CO2, were measured for attached and excised flowers.
Flower age affected all nectar traits, whilst temperature affected total nectar sugar only. Increased light reduced floral CO2 efflux, increased nectar sugar production, and affected the ratio of DHA to other nectar sugars. DCMU, an inhibitor of photosystem II, reduced nectar sugar production. Pyridoxal phosphate, an inhibitor of the chloroplast envelope triose phosphate transporter, reduced nectar DHA content. Incubation of excised flowers with 13CO2 in the light resulted in enrichment of nectar sugars, including DHA.
Photosynthesis within green nectaries contributes to nectar sugars and influences nectar composition. Mānuka nectar DHA arises from pools of triose phosphate that are modulated by nectary photosynthesis.

year: 2021-08-24

title: Mobile phone use while driving after a new national law in New Zealand

authors: Starkey, Nicola J.

abstract: Mobile phone use while driving leads to impairments in driver performance including slowed reaction times, poor lane keeping and reduced hazard detection. To increase public safety, in 2009 the New Zealand (NZ) Government introduced a ban on the use of hand-held phones while driving. The aim of the current to study was to identify the post-law prevalence of phone use while driving. Observers recorded drivers’ mobile phone use at or near traffic lights and in moving traffic at three locations (Central Business District, and two suburbs of contrasting area-based deprivation) in Wellington, NZ. A total of 8335 cars at traffic lights and 9520 cars in moving traffic were systematically observed. The use of mobile phones by drivers at these locations were 1.87% (95%CI: 1.60-2.18) and 1.34% (95%CI: 1.13-1.59) respectively. Younger drivers (<25 years) were significantly more likely to use their phones compared to older drivers (e.g., in moving traffic, risk ratio = 2.91, 95%CI=2.00–4.22). Overall, it was much more common for drivers to use their phones in a “non-ear position” (77.8%) than next to their ear, and this was also significantly higher among younger drivers. These data suggest that there has been a decline in phone use when driving as compared to rates of 3.9% reported in a pre-law study (in Auckland). Although these findings are encouraging, phone use while driving is still relatively high. Options such as mass media campaigns, enhanced enforcement, and higher penalties for breaking the law may need to be considered to further address this issue.

text: Mobile phone use while driving after a new national law in New Zealand Mobile phone use while driving leads to impairments in driver performance including slowed reaction times, poor lane keeping and reduced hazard detection. To increase public safety, in 2009 the New Zealand (NZ) Government introduced a ban on the use of hand-held phones while driving. The aim of the current to study was to identify the post-law prevalence of phone use while driving. Observers recorded drivers’ mobile phone use at or near traffic lights and in moving traffic at three locations (Central Business District, and two suburbs of contrasting area-based deprivation) in Wellington, NZ. A total of 8335 cars at traffic lights and 9520 cars in moving traffic were systematically observed. The use of mobile phones by drivers at these locations were 1.87% (95%CI: 1.60-2.18) and 1.34% (95%CI: 1.13-1.59) respectively. Younger drivers (<25 years) were significantly more likely to use their phones compared to older drivers (e.g., in moving traffic, risk ratio = 2.91, 95%CI=2.00–4.22). Overall, it was much more common for drivers to use their phones in a “non-ear position” (77.8%) than next to their ear, and this was also significantly higher among younger drivers. These data suggest that there has been a decline in phone use when driving as compared to rates of 3.9% reported in a pre-law study (in Auckland). Although these findings are encouraging, phone use while driving is still relatively high. Options such as mass media campaigns, enhanced enforcement, and higher penalties for breaking the law may need to be considered to further address this issue.

year: 2013-08-28

title: Angitūtanga o ngā tauira Māori:  Supporting Māori students to succeed in psychology

authors: Martin, Dionne

subjects: Psychology

abstract: Many Māori seek out university degrees to make a meaningful impact on the health of their community. Psychology, is one avenue that attracts Māori to do so. Psychology training has often failed to meet the needs of Māori students, often creating barriers to Māori student success. This thesis will explore barriers and support mechanisms that Māori students experience while attending university in pursuit of psychology degrees. This study will focus on experiences had by those enrolled in The School of Psychology at The Univeristy of Waikato, on the Hamilton campus. Informed by kaupapa Māori guidelines and analysed though the use of pūrākau this thesis highlights some key experiences shared by Māori psychology students. Three key experiences were identified. First, the prominence of Western culture in The School of psychology and the impact that has on Māori sense of belonging and whanaungatanga. Second, support system realities for Māori, identifying key university supports systems and realities associated with ones home environment. Third, the transitional journey to becoming a psychologist and what impact that has on the university journey. With this in mind, some recommendations are made to support Māori student success in psychology. These recommendations advocate for the provision of a more bicultural learning experience, creation of a culturally affirming environment, recruitment and retention of culturally capable staff, appropriate resourcing, funding and training for support services, better support for Māori realities and pathway navigation support.

text: Angitūtanga o ngā tauira Māori:  Supporting Māori students to succeed in psychology Many Māori seek out university degrees to make a meaningful impact on the health of their community. Psychology, is one avenue that attracts Māori to do so. Psychology training has often failed to meet the needs of Māori students, often creating barriers to Māori student success. This thesis will explore barriers and support mechanisms that Māori students experience while attending university in pursuit of psychology degrees. This study will focus on experiences had by those enrolled in The School of Psychology at The Univeristy of Waikato, on the Hamilton campus. Informed by kaupapa Māori guidelines and analysed though the use of pūrākau this thesis highlights some key experiences shared by Māori psychology students. Three key experiences were identified. First, the prominence of Western culture in The School of psychology and the impact that has on Māori sense of belonging and whanaungatanga. Second, support system realities for Māori, identifying key university supports systems and realities associated with ones home environment. Third, the transitional journey to becoming a psychologist and what impact that has on the university journey. With this in mind, some recommendations are made to support Māori student success in psychology. These recommendations advocate for the provision of a more bicultural learning experience, creation of a culturally affirming environment, recruitment and retention of culturally capable staff, appropriate resourcing, funding and training for support services, better support for Māori realities and pathway navigation support.

year: 2025